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Versions: 00 01 02 03 04 05 06 07 RFC 6497

Internet Engineering Task Force                                 M. Davis
Internet-Draft                                                    Google
Intended status: Informational                               A. Phillips
Expires: March 28, 2012                                           Lab126
                                                               Y. Umaoka
                                                                     IBM
                                                                 C. Falk
                                                       Infinite Automata
                                                      September 25, 2011


                BCP 47 Extension T - Transformed Content
                      draft-davis-t-langtag-ext-06

Abstract

   This document specifies an Extension to BCP 47 which provides subtags
   for specifying the source language or script of transformed content,
   including content that has been transliterated, transcribed, or
   translated, or in some other way influenced by the source.  It also
   provides for additional information used for identification.

Status of this Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on March 28, 2012.

Copyright Notice

   Copyright (c) 2011 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents



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   carefully, as they describe your rights and restrictions with respect
   to this document.


Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
     1.1.  Requirements Language  . . . . . . . . . . . . . . . . . .  4
   2.  BCP47 Required Information . . . . . . . . . . . . . . . . . .  4
     2.1.  Overview . . . . . . . . . . . . . . . . . . . . . . . . .  4
     2.2.  Structure  . . . . . . . . . . . . . . . . . . . . . . . .  6
     2.3.  Canonicalization . . . . . . . . . . . . . . . . . . . . .  7
     2.4.  BCP47 Registration Form  . . . . . . . . . . . . . . . . .  8
     2.5.  Field Definitions  . . . . . . . . . . . . . . . . . . . .  8
     2.6.  Registration of Field Subtags  . . . . . . . . . . . . . . 10
     2.7.  Registration of Additional Fields  . . . . . . . . . . . . 10
     2.8.  Committee Responses to Registration Proposals  . . . . . . 10
     2.9.  Machine-Readable Data  . . . . . . . . . . . . . . . . . . 11
   3.  Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 13
   4.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 14
   5.  Security Considerations  . . . . . . . . . . . . . . . . . . . 14
   6.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 14
     6.1.  Normative References . . . . . . . . . . . . . . . . . . . 14
     6.2.  Informative References . . . . . . . . . . . . . . . . . . 14
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 15


























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1.  Introduction

   [BCP47] permits the definition and registration of language tag
   extensions "that contain a language component and are compatible with
   applications that understand language tags".  This document defines
   an extension for specifying the source of content that has been
   transformed, including text that has been transliterated,
   transcribed, or translated, or in some other way influenced by the
   source.  It may be used in queries to request content that has been
   transformed.  The "singleton" identifier for this extension is 't'.

   Language tags, as defined by [BCP47], are useful for identifying the
   language of content.  There are mechanisms for specifying variant
   subtags for special purposes.  However, these variants are
   insufficient for specifying content that has undergone
   transformations, including content that has been transliterated,
   transcribed, or translated.  The correct interpretation of the
   content may depend upon knowledge of the conventions used for the
   transformation.

   Suppose that Italian or Russian cities on a map are transcribed for
   Japanese users.  Each name needs to be transliterated into katakana
   using rules appropriate for the specific source and target language.
   When tagging such data, it is important to be able to indicate not
   only the resulting content language ("ja" in this case), but also the
   source language.

   Transforms such as transliterations may vary depending not only on
   the basis of the source and target script, but also on the source and
   target language.  Thus the Russian <U+041F U+0443 U+0442 U+0438
   U+043D> (which corresponds to the Cyrillic <PE, U, TE, I, EN>)
   transliterates into "Putin" in English but "Poutine" in French.  The
   identifier could be used to indicate a desired mechanical
   transformation in an API, or could be used to tag data that has been
   converted (mechanically or by hand) according to a transliteration
   method.

   In addition, many different conventions have arisen for how to
   transform text, even between the same languages and scripts.  For
   example, "Gaddafi" is commonly transliterated from Arabic to English
   as any of (G/Q/K/Kh)a(d/dh/dd/dhdh/th/zz)af(i/y).  Some examples of
   standardized conventions used for transcribing or transliterating
   text include:

   a.  United Nations Group of Experts on Geographical Names (UNGEGN)

   b.  US Library of Congress (LOC)




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   c.  US Board on Geographic Names (BGN)

   d.  Korean Ministry of Culture, Sports and Tourism (MCST)

   e.  International Organization for Standardization (ISO)

   The usage of this extension is not limited to formal transformations,
   and may include other instances where the content is in some other
   way influenced by the source.  For example, this extension could be
   used to designate a request for a speech recognizer that is tailored
   specifically for 2nd-language speakers who are 1st-language speakers
   of a particular language (e.g. a recognizer for "English spoken with
   a Chinese accent").

1.1.  Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119.


2.  BCP47 Required Information

2.1.  Overview

   Identification of transformed content can be done using the 't'
   extension defined in this document.  This extension is formed by the
   't' singleton followed by a sequence of subtags that would form a
   language tag as defined by [BCP47].  This allows for the source
   language or script to be specified to the degree of precision
   required.  There are restrictions on the sequence of subtags.  They
   MUST form a regular, valid, canonical language tag, and MUST neither
   include extensions nor private use sequences introduced by the
   singleton 'x'.  Where only the script is relevant (such as
   identifying a script-script transliteration) then 'und' is used for
   the primary language subtag.

   For example:

   +---------------------+---------------------------------------------+
   | Language Tag        | Description                                 |
   +---------------------+---------------------------------------------+
   | ja-t-it             | The content is Japanese, transformed from   |
   |                     | Italian.                                    |
   | ja-Kana-t-it        | The content is Japanese Katakana,           |
   |                     | transformed from Italian.                   |





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   | und-Latn-t-und-cyrl | The content is in the Latin script,         |
   |                     | transformed from the Cyrillic script.       |
   +---------------------+---------------------------------------------+

   Note that the sequence of subtags governed by 't' cannot contain a
   singleton (a single-character subtag), because that would start a new
   extension.  For example, the tag "ja-t-i-ami" does not indicate that
   the source is in "i-ami", because "i-ami" is not a regular language
   tag in [BCP47].  That tag would express an empty 't' extension
   followed by an 'i' extension.

   The t extension is not intended for use in structured data that
   already provides separate source and target language identifiers.
   For example, this is the case in localization interchange formats
   such as XLIFF.  In such cases, it would be inappropriate to use "ja-
   t-it" for the target language tag because the source language tag
   "it" would already be present in the data.  Instead one would use the
   language tag "ja".

   As noted earlier, it is sometimes necessary to indicate additional
   information about a transformation.  This additional information is
   optionally supplied after the source in a series of one or more
   fields, where each field consists of a field separator subtag
   followed by one or more non-separator subtags.  Each field separator
   subtag consists of a single letter followed by a single digit.

   A transformation mechanism is an optional field that indicates the
   specification used for the transformation, such as "UNGEGN" for the
   the United Nations Group of Experts on Geographical Names
   transliterations and transcriptions.  It uses the 'm0' field
   separator followed by certain subtags.

   For example:

   +------------------------------------+------------------------------+
   | Language Tag                       | Description                  |
   +------------------------------------+------------------------------+
   | und-Cyrl-t-und-latn-m0-ungegn-2007 | the content is in Cyrillic,  |
   |                                    | transformed from Latn,       |
   |                                    | according to a UNGEGN        |
   |                                    | specification dated 2007.    |
   +------------------------------------+------------------------------+

   The field separator subtags such as 'm0' were chosen because they are
   short, visually distinctive, and cannot occur in a language subtag
   (outside of an extension and after 'x'), thus eliminating the
   potential for collision or confusion with the source language tag.




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   The field subtags are defined by Section 3 [1] of Unicode Technical
   Standard #35: Unicode Locale Data Markup Language [UTS35].  As
   required by BCP 47, subtags follow the language tag ABNF and other
   rules for the formation of language tags and subtags, are restricted
   to the ASCII letters and digits, are not case sensitive, and do not
   exceed eight characters in length.

   EDITORIAL NOTE: This new facility has been accepted by the Unicode
   CLDR committee for incorporation into the next version of Unicode
   CLDR, parallel with the structure of the 'u' extension [RFC6067], for
   which it is already the maintaining authority.  The data and
   specification will be available by the time this internet draft has
   been approved.

   LDML is available over the Internet and at no cost, and is available
   via a royalty-free license at http://unicode.org/copyright.html.
   LDML is versioned, and each version of LDML is numbered, dated, and
   stable.  Extension subtags, once defined by LDML, are never retracted
   or substantially changed in meaning.

   The maintaining authority for the 't' extension is the Unicode
   Consortium:

   +---------------+---------------------------------------------------+
   | Item          | Value                                             |
   +---------------+---------------------------------------------------+
   | Name          | Unicode Consortium                                |
   | Contact Email | cldr-contact@unicode.org                          |
   | Discussion    | cldr-users@unicode.org                            |
   | List Email    |                                                   |
   | URL Location  | cldr.unicode.org                                  |
   | Specification | Unicode Technical Standard #35 Unicode Locale     |
   |               | Data Markup Language (LDML),                      |
   |               | http://unicode.org/reports/tr35/                  |
   | Section       | Section 3 Unicode Language and Locale Identifiers |
   +---------------+---------------------------------------------------+

2.2.  Structure

   The subtags in the 't' extension are of the following form:











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   t-ext=    "t"                      ; Extension
             (("-" lang *("-" field)) ; Source + optional field(s)
             / 1*("-" field))         ; Field(s) only (no source)

   lang=     language                 ; BCP47, with restrictions
             ["-" script]
             ["-" region]
             *("-" variant)

   field=    sep 1*("-" 3*8alphanum)  ; With restrictions

   sep=      ALPHA DIGIT              ; Subtag separators
   alphanum= ALPHA / DIGIT

   where <language>, <script>, <region>, and <variant> rules are
   specified in [BCP47], <ALPHA> and <DIGIT> rules - in [RFC5234].

   Description and restrictions:

   a.  The 't' extension MUST have at least one subtag.

   b.  The 't' extension normally starts with a source language tag,
       which MUST be a regular, canonical language tag as specified by
       [BCP47].  Tags described by the 'irregular' production in BCP 47
       MUST NOT be used to form the language tag.  The source language
       tag MAY be omitted: some field values do not require it.

   c.  There is optionally a sequence of fields, where each field has a
       separator followed by a sequence of one or more subtags.  Two
       identical field separators MUST NOT be present in the language
       tag.

   d.  The order of the fields in a t extension is not significant.  The
       order of subtags within a field is significant.  (See Section 2.3
       Canonicalization.)

   e.  The 't' subtag fields are defined by Section 3 [1] of Unicode
       Technical Standard #35: Unicode Locale Data Markup Language
       [UTS35].

2.3.  Canonicalization

   As required by [BCP47], the use of uppercase or lowercase letters is
   not significant in the subtags used in this extension.  The canonical
   form for all subtags in the extension is lowercase, with the fields
   ordered by the separators, alphabetically.  The order of subtags
   within a field is significant, and MUST NOT be changed in the process
   of canonicalizing.



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2.4.  BCP47 Registration Form

   Per RFC 5646, Section 3.7 [BCP47]:

   %%
   Identifier: t
   Description: Specifying Transformed Content
   Comments: Subtags for the identification of content that has been
   transformed, including but not limited to:
   transliteration, transcription, and translation.
   Added: 2010-mm-dd
   RFC: [TBD]
   Authority: Unicode Consortium
   Contact_Email: cldr-contact@unicode.org
   Mailing_List: cldr-users@unicode.org
   URL: http://www.unicode.org/Public/cldr/latest/core.zip
   %%

2.5.  Field Definitions

   Assignment of 't' field subtags is determined by the Unicode CLDR
   Technical Committee, in accordance with the policies and procedures
   in http://www.unicode.org/consortium/tc-procedures.html, and subject
   to the Unicode Consortium Policies on
   http://www.unicode.org/policies/policies.html.

   Assignments that can be made by successive versions of LDML [UTS35]
   by the Unicode Consortium without requiring a new RFC include:

   o  The allocation of new field separator subtags for use after the
      't' extension.

   o  The allocation of subtags valid after a field separator subtag.

   o  The addition of subtag aliases and descriptions.

   o  The modification of subtag descriptions.

   Changes to the syntax or meaning of the 't' extension would require a
   new RFC that obsoletes this document; such an RFC would break
   stability, and would thus be contrary to the policies of the Unicode
   Consortium.

   At the time this document was published, one field was specified in
   [UTS35]: the transform mechanism.  That field is summarized here:

   a.  The transform mechanism consists of a sequence of subtags
       starting with the 'm0' separator followed by one or more



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       mechanism subtags.  Each mechanism subtag has a length of 3 to 8
       alphanumeric characters.  The sequence as a whole provides an
       identification of the specification for the transform, such as
       the mechanism subtag 'ungegn' in "und-Cyrl-t-und-latn-m0-ungegn".
       In many cases, only one mechanism subtag is necessary, but
       multiple subtags MAY be defined in [UTS35] where necessary.

   b.  Any purely numeric subtag is a representation of a date in the
       Gregorian calendar.  It MAY occur in any mechanism field, but it
       SHOULD only be used where necessary.  If it does occur:

       *  it MUST occur as the final subtag in the field

       *  it MUST NOT be the only subtag in the field

       *  it MUST consist of a sequence of digits of the form YYYY,
          YYYYMM, or YYYYMMDD

       *  it SHOULD be as short as possible

       Examples:

       *  20110623 represents June 23rd, 2011.

       *  There are 3 dated versions of the UNGEGN transliteration
          specification for Hebrew to Latin.  They can be represented by
          the following language tags:

          +  und-Hebr-t-und-Latn-m0-ungegn-1972

          +  und-Hebr-t-und-Latn-m0-ungegn-1977

          +  und-Hebr-t-und-Latn-m0-ungegn-2007

       *  Suppose that the BGN transliteration specification for
          Cyrillic to Latin had three versions, dated June 11th, 1999;
          Dec 30th, 1999; and May 1st, 2011.  In that case, the
          corresponding first two DATE subtags would require months to
          be distinctive (199906 and 199912), but the last subtag would
          only require the year (2011).

   c.  Some mechanisms may use a versioning system that is not
       distinguished by date, or not by date alone.  In the latter case,
       the version will be of a form specified by [UTS35] for that
       mechanism.  For example, if the mechanism XXX uses versions of
       the form v21a, then a tag could look like "ja-t-it-m0-xxx-v21a".
       If there are multiple subversions distinguished by date, then a
       tag could look like "ja-t-it-m0-xxx-v21a-2007".



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   A language tag with the t extension MAY be used to request a specific
   transform of content.  In such a case, the recipient SHOULD return
   content that corresponds as closely as feasible to the requested
   transform, including the specification of the mechanism.  For
   example, if the request is ja-t-it-m0-xxx-v21a-2007, and the
   recipient has content corresponding to both ja-t-it-m0-xxx-v21a and
   ja-t-it-m0-xxx-v21b-2009, then the v21a version would be preferred.
   As is the case for language matching as discussed in [BCP47],
   different implementations MAY have different measures of "closeness".

2.6.  Registration of Field Subtags

   Registration of transform mechanisms is requested by filing a ticket
   at cldr.unicode.org [2].  The proposal in the ticket MUST contain the
   following information:

   +-------------+-----------------------------------------------------+
   | Item        | Description                                         |
   +-------------+-----------------------------------------------------+
   | Subtag      | The proposed mechanism subtag (or subtag sequence). |
   | Description | A description of the proposed mechanism; that       |
   |             | description MUST be sufficient to distinguish it    |
   |             | from other mechanisms in use.                       |
   | Version     | If versioning for the mechanism is not done         |
   |             | according to date, then a description of the        |
   |             | versioning conventions used for the mechanism.      |
   +-------------+-----------------------------------------------------+

   Proposals for clarifications of descriptions or additional aliases
   may also be requested by filing a ticket.

   The committee MAY define a template for submissions that requests
   more information, if it is found that such information would be
   useful in evaluating proposals.

2.7.  Registration of Additional Fields

   In the event that it proves necessary to add an additional field
   (such as 'm2'), it can be requested by filing a ticket at
   cldr.unicode.org [2].  The proposal in the ticket MUST contain a full
   description of the proposed field semantics and subtag syntax, and
   MUST be conform to the ABNF syntax for "field" presented in
   Section 2.2.

2.8.  Committee Responses to Registration Proposals

   The committee MUST post each proposal publicly within 2 weeks after
   reception, to allow for comments.  The committee must respond



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   publicly to each proposal within 4 weeks after reception.

   The response MAY:

   o  request more information or clarification

   o  accept the proposal, optionally with modifications to the subtag
      or description

   o  reject the proposal, because of significant objections raised on
      the mailing list or due to problems with constraints in this
      document or in [UTS35]

   Accepted tickets result in a new entry in the machine-readable CLDR
   BCP47 data, or in the case of a clarified description, modifications
   to the description attribute value for an existing entry.

2.9.  Machine-Readable Data

   EDITORIAL NOTE: The following parallels the structure used for the
   'u' extension [RFC6067], for which the Unicode Consortium is the
   maintaining authority.  The data and specification will be available
   by the time this internet draft has been approved.  The description
   field is in the process of being added to CLDR.

   Beginning with CLDR version 1.7.2, machine-readable files are
   available listing the data defined for BCP47 extensions for each
   successive version of [UTS35].  These releases are listed on
   http://cldr.unicode.org/index/downloads.  Each release has an
   associated data directory of the form
   "http://unicode.org/Public/cldr/<version>", where "<version>" is
   replaced by the release number.  For example, for version 1.7.2, the
   "core.zip" file is located at
   http://unicode.org/Public/cldr/1.7.2/core.zip [3].  The most recent
   version is always identified by the version "latest" and can be
   accessed by the URL in Section 2.4.

   Inside the "core.zip" file, the directory "common/bcp47" contains the
   data files listing the valid attributes, keys, and types for each
   successive version of [UTS35].  Each data file list the keys and
   types relevant to that topic.  For example, mechanism.xml contains
   the subtags (types) for the t mechanisms.

   The XML structure lists the keys, such as <key extension="t"
   name="m0" alias="collation" description="Transliteration extension
   mechanism">, with subelements for the types, such as <type
   name="ungegn" description="United Nations Group of Experts on
   Geographical Names"/>.  The currently defined attributes for the



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   mechanisms include:

   +-------------+-------------------------------+---------------------+
   | Attribute   | Description                   | Examples            |
   +-------------+-------------------------------+---------------------+
   | name        | The name of the mechanism,    | UNGEGN, ALALC       |
   |             | limited to 3-8 characters (or |                     |
   |             | sequences of them).           |                     |
   | description | A description of the name,    | United Nations      |
   |             | with all and only that        | Group of Experts on |
   |             | information necessary to      | Geographical Names; |
   |             | distinguish one name from     | American Library    |
   |             | others with which it might be | Association-Library |
   |             | confused.  Descriptions are   | of Congress         |
   |             | not intended to provide       |                     |
   |             | general background            |                     |
   |             | information.                  |                     |
   | since       | Indicates the first version   | 1.9, 2.0.1          |
   |             | of CLDR where the name        |                     |
   |             | appears.  (Required for new   |                     |
   |             | items.)                       |                     |
   | alias       | Alternative name of the key   |                     |
   |             | or type, not limited in       |                     |
   |             | number of characters.         |                     |
   |             | Aliases are intended for      |                     |
   |             | backwards compatibility, not  |                     |
   |             | to provide all possible       |                     |
   |             | alternate names or            |                     |
   |             | designations.  (Optional)     |                     |
   +-------------+-------------------------------+---------------------+

   The file for the transform extension is "transform.xml".  The initial
   version of that file contains the following information.


















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   <key extension="t" name="m0" description=
         "Transliteration extension mechanism"/>
      <type name="ungegn" description=
         "United Nations Group of Experts on Geographical Names"/>
      <type name="alaloc" description=
         "American Library Association-Library of Congress"/>
      <type name="bgn" description=
         "US Board on Geographic Names"/>
      <type name="mcst" description=
         "Korean Ministry of Culture, Sports and Tourism"/>
      <type name="iso" description=
         "International Organization for Standardization"/>
      <type name="din" description=
         "Deutsches Institut fuer Normung"/>
      <type name="gost" description=
         "Euro-Asian Council for Standardization, Metrology
          and Certification"/>
   </key>

   To get the version information in XML when working with the data
   files, the XML parser must be validating.  When the 'core.zip' file
   is unzipped, the 'dtd' directory will be at the same level as the
   'bcp47' directory; that is required for correct validation.  For each
   release after CLDR 1.8, types introduced in that release are also
   marked in the data files by the XML attribute "since", such as in the
   following example:
   <type name="adp" since="1.9"/>

   The data is also currently maintained in a source code repository,
   with each release tagged, for viewing directly without unzipping.
   For example, see:

   o  http://unicode.org/repos/cldr/tags/release-1-7-2/common/bcp47/

   o  http://unicode.org/repos/cldr/tags/release-1-8/common/bcp47/

   For more information, see
   http://cldr.unicode.org/index/bcp47-extension.


3.  Acknowledgements

   Thanks to John Emmons and the rest of the Unicode CLDR Technical
   Committee for their work in developing the BCP 47 subtags for LDML.







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4.  IANA Considerations

   This document will require IANA to insert the record of Section 2.4
   into the Language Extensions Registry, according to Section 3.7,
   Extensions and the Extensions Registry of "Tags for Identifying
   Languages" in [BCP47].  Per Section 5.2 of [BCP47], there might be
   occasional (rare) requests by the Unicode Consortium (the "Authority"
   listed in the record) for maintenance of this record.  Changes that
   can be submitted to IANA without the publication of a new RFC are
   limited to modification of the Comments, Contact_Email, Mailing_List,
   and URL fields.  Any such requested changes MUST use the domain
   'unicode.org' in any new addresses or URIs, MUST explicitly cite this
   document (so that IANA can reference these requirements), and MUST
   originate from the 'unicode.org' domain.  The domain or authority can
   only be changed via a new RFC.

   This document does not require IANA to create or maintain a new
   registry or otherwise impact IANA.


5.  Security Considerations

   The security considerations for this extension are the same as those
   for [BCP47].  See RFC 5646, Section 6, Security Considerations
   [BCP47].


6.  References

6.1.  Normative References

   [BCP47]    Davis, M., Ed. and A. Phillips, Ed., "Tags for the
              Identification of Language (BCP47)", September 2009.

   [RFC5234]  Crocker, Ed., "Augmented BNF for Syntax Specifications:
              ABNF", 2008.

   [RFC6067]  Davis, M., Ed., Phillips, A., Ed., and Y. Umaoka, Ed.,
              "BCP 47 Extension U", September 2010.

   [UTS35]    Davis, M., "Unicode Technical Standard #35: Locale Data
              Markup Language (LDML)", December 2007,
              <http://www.unicode.org/reports/tr35/>.

6.2.  Informative References

   [ldml-registry]
              "Registry for Common Locale Data Repository tag elements",



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Internet-Draft             BCP 47 Extension T             September 2011


              September 2009.

URIs

   [1]  <http://unicode.org/reports/tr35/>

   [2]  <http://cldr.unicode.org/>

   [3]  <http://unicode.org/Public/cldr/1.7.2/>


Authors' Addresses

   Mark Davis
   Google

   Email: mark@macchiato.com


   Addison Phillips
   Lab126

   Email: addison@lab126.com


   Yoshito Umaoka
   IBM

   Email: yoshito_umaoka@us.ibm.com


   Courtney Falk
   Infinite Automata

   Email: court@infiauto.com
















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