Reference LGR for script: Armenian (Armn) | lgr-second-level-armenian-script-24jan24-en |
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This document is mechanically formatted from the above XML file for the LGR. It provides additional summary data and explanatory text. The XML file remains the sole normative specification of the LGR.
Date | 2024-01-24 |
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LGR Version | 1 (Second Level Reference LGR) |
Language | und-Armn (Armenian Script) |
Unicode Version | 11.0.0 |
Description
INSTRUCTIONS
- These instructions cover how to adopt an LGR based on this reference LGR for a given zone and how to prepare the file for deposit in the IANA Repository of IDN Practices.
- As described the IANA procedure
(https://www.iana.org/help/idn-repository-procedure)
an LGR MUST contain the following elements in its header:- Script or Language Designator (see below for guidance)
- Version Number (this must increase with each amendment to the LGR, even if the updates are limited to the header itself)
- Effective Date (the date at which the policy becomes applicable in operational use)
- Registry Contact Details (contact name, email address, and/or phone number)
- The following information is optional:
- Document creation date
- Applicable Domain(s)
- Changes made to the Reference LGR before adopting
Please add or modify the following items in the XML source code for this file before
depositing the document in the IANA Repository.
(https://www.iana.org/domains/idn-tables)
Meta Data
Note: version numbers start at 1. RFC 7940 recommends using simple integers. The version comment is optional, please replace or delete the default comment. Version comments may be used by some tools as part of the page header.
<version comment="
[Please replace (or delete) the optional comment]">
[Please fill in version number, starting at 1]</version>
<date>
[Please fill in with publication date, in YYYY-MM-DD format]</date>
<validity-start>
[Please fill in effective date, in YYYY-MM-DD format]</validity-start>
Note: the scope element may be repeated, so that the same document can serve for multiple domains.
<scope type="domain">
[Please provide, in ".domain" format]</scope>
Registry Contact Information:
Please fill in the Registry Contact Details.
Change History
If you made technical modifications to the LGR, please summarize them in the Change History (and also note the details in the appropriate section of the description).
PLEASE DELETE THESE INSTRUCTIONS BEFORE DEPOSITING THE DOCUMENT
Registry Contact Details
- Contact Name: [Please fill in Contact Name]
- Email address: [Please fill in Email address]
- Phone Number: [Please fill in optional Phone Number]
Label Generation Rules for the Armenian Script
Overview
This document specifies a set of Label Generation Rules (LGR) for the Armenian script for the second level domain or domains identified above. The starting point for the development of this LGR can be found in the related Root Zone LGR [RZ-LGR-Armn]. The format of this file follows [RFC 7940]. This LGR is adapted from the “Reference LGR for the Second Level for the Armenian Script” [Ref-LGR-und-Armn], for details, see Change History below.
For details and additional background on the Armenian script, see “Proposal for a Armenian Script Root Zone LGR” [Proposal-Armenian].
Repertoire
According to [Proposal-Armenian], the repertoire contains the 38 code points in the range U+0561 ա–U+0586 ֆ and supports the Armenian language as written in the Armenian script. The repertoire is a subset of [Unicode 11.0.0]. For details, see Section 5, “Repertoire” in [Proposal-Armenian]. (The proposal cited has been adopted for the Armenian script portion of the Root Zone LGR.)
For the second level, the repertoire has been augmented with the ASCII digits, U+0030 0 to U+0039 9, plus U+002D - HYPHEN-MINUS, for a total of 49 repertoire elements.
Any code points outside the Armenian Script repertoire that are targets for out-of-repertoire variants would be included here only if the variant is listed in this file. In this case they are identified as a reflexive (identity) variant of type “out-of-repertoire-var”. Whether or not they are listed, they do not form part of the repertoire.
Repertoire Listing: Each code point or range is tagged with the script or scripts with which the code point is used, and one or more references documenting sufficient justification for inclusion in the repertoire, see “References” below. For code points that are part of the repertoire, comments identify the languages using the code point.
Variants
This LGR defines no in-script variants within the Armenian script.
The variants defined in this LGR are limited to those required for use in zones not shared with any other script. As such, this LGR does not define cross-script variants. However, using this LGR concurrently with any LGR for Latin, Greek, and Cyrillic in the same zone will introduce some in-script variants due to cross-script variant transitivity. This will also create potential cross-script issues when used with the same LGRs. For details, see Section 6, “Variants” in [Proposal-Armenian]. Mitigation of these in-script and cross-script variants can be addressed by using the Common LGR. For details, see Section 3, “Use of Multiple Reference LGRs in the Same Zone” in [Level-2-Overview]. In addition to variants defined by this LGR, the full variant information related to this script and added by concurrent use with the Latin, Greek, and Cyrillic LGR(s) can be found in the following LGR: [Ref-LGR-Latin-Full-Variant-Script]
In particular, the Armenian LGR will inherit the following in-script variant as result of concurrent use with the Latin and Greek LGRs:
- Blocked: U+0572 ղ — U+0578 ո.
This variant is required when using this LGR together with the Common LGR in label processing, but it also reflects a certain consistency in the approach to variants across typographically related scripts. The variant can be removed if using this LGR strictly as standalone.
Variant Disposition: All variants are of type “blocked”, making labels that differ only by these variants mutually exclusive: whichever label containing either of these variants is chosen earlier would be delegated, while any other equivalent labels should be blocked. There is no preference among these labels.
This LGR does not define allocatable variants.
The specification of variants in this LGR follows the guidelines in [RFC 8228].
Character Classes
This LGR does not define named character classes.
Whole Label Evaluation (WLE) and Context Rules
Default Whole Label Evaluation Rules
By default, the LGR includes the rules and actions to implement the following restrictions mandated by the IDNA protocol. They are marked with ⍟.
- Hyphen Restrictions — restrictions on the allowable placement of hyphens (no leading/ending hyphen and no hyphen in positions 3 and 4). These restrictions are described in Section 4.2.3.1 of RFC 5891 [150]. They are implemented here as context rule on U+002D (-) HYPHEN-MINUS.
- Leading Combining Marks — restrictions on the allowable placement of combining marks (no leading combining mark). This rule is described in Section 4.2.3.2 of RFC 5891 [150].
Armenian-specific Rules
This LGR does not define rules specific to the Armenian script.
Actions
This LGR includes the default actions for LGRs as well as the action needed to invalidate labels with misplaced combining marks. They are marked with ⍟. For a description see [RFC 7940].
Methodology and Contributors
The LGR in this document has been adapted from the corresponding Reference LGR for the Second Level. The Second Level Reference LGR for the Armenian Script was developed by Michel Suignard and Asmus Freytag, based on the Root Zone LGR for the Armenian script and information contained or referenced therein; see [RZ-LGR-Armn]. Suitable extensions for the second level have been applied according to the [Guidelines] and with community input. The original proposal for a Root Zone LGR for the Armenian script, that this LGR is based on, was developed by the Armenian Generation Panel. For more information on methodology and contributors to the underlying Root Zone LGR, see Sections 4 and 8 in [Proposal-Armenian], as well as [RZ-LGR-Overview].
Changes from Version Dated 24 January 2024
Adopted from the Second Level Reference LGR for the Armenian Script [Ref-LGR-und-Armn] without normative changes.
References
The following general references are cited in this document:
- [Guidelines]
- ICANN, “Guidelines for Developing Reference LGRs for the Second Level”, (Los Angeles, California: ICANN, 27 May 2020),
https://www.icann.org/en/system/files/files/lgr-guidelines-second-level-27may20-en.pdf - [Level-2-Overview]
- Internet Corporation for Assigned Names and Numbers, (ICANN),“Reference Label Generation Rules (LGR) for the Second Level: Overview and Summary” (PDF),
(Los Angeles, California: ICANN, 24 January 2024),
https://www.icann.org/en/system/files/files/level2-lgr-overview-summary-24jan24-en.pdf - [MSR-5]
- Integration Panel, “Maximal Starting Repertoire — MSR-5 Overview and Rationale”, 24 June 2021,
https://www.icann.org/en/system/files/files/msr-5-overview-24jun21-en.pdf - [Proposal-Armenian]
- Armenian Generation Panel, “Proposal for an Armenian Script Root Zone LGR”, 5 November 2015,
https://www.icann.org/en/system/files/files/armenian-lgr-proposal-05nov15-en.pdf - [Ref-LGR-und-Armn]
- ICANN, Second Level Reference Label Generation Rules for the Armenian Script (und-Armn), 24 January 2024 (XML)
https://www.icann.org/sites/default/files/packages/lgr/lgr-second-level-armenian-script-24jan24-en.xml
non-normative HTML presentation:
https://www.icann.org/sites/default/files/packages/lgr/lgr-second-level-armenian-script-24jan24-en.html - [Ref-LGR-Latin-Full-Variant-Script]
- ICANN, Second Level Reference Label Generation Rules for the Latin Script (und-Latn), 24 January 2024 (XML)
https://www.icann.org/sites/default/files/packages/lgr/lgr-second-level-latin-full-variant-script-24jan24-en.xml
non-normative HTML presentation:
https://www.icann.org/sites/default/files/packages/lgr/lgr-second-level-latin-full-variant-script-24jan24-en.html - [RZ-LGR-Armn]
- ICANN, Root Zone Label Generation Rules for the Armenian Script (und-Armn), 26 May 2022 (XML)
https://www.icann.org/sites/default/files/lgr/rz-lgr-5-armenian-script-26may22-en.xml - [RZ-LGR-Overview]
- Integration Panel, “Root Zone Label Generation Rules (RZ LGR-5): Overview and Summary”, 26 May 2022 (PDF),
https://www.icann.org/sites/default/files/lgr/rz-lgr-5-overview-26may22-en.pdf - [RZ-LGR-5]
- Integration Panel, “Root Zone Label Generation Rules (RZ-LGR-5)”, 26 May 2022 (XML),
https://www.icann.org/sites/default/files/lgr/rz-lgr-5-common-26may22-en.xml
non-normative HTML presentation:
https://www.icann.org/sites/default/files/lgr/rz-lgr-5-common-26may22-en.html - [RFC 7940]
- Davies, K. and A. Freytag, “Representing Label Generation Rulesets Using XML”,
RFC 7940, August 2016,
https://www.rfc-editor.org/info/rfc7940 - [RFC 8228]
- A. Freytag, “Guidance on Designing Label Generation Rulesets (LGRs) Supporting Variant Labels”, RFC 8228, August 2017,
https://www.rfc-editor.org/info/rfc8228 - [Unicode 11.0.0]
- The Unicode Consortium. The Unicode Standard, Version 11.0.0, (Mountain View, CA: The Unicode Consortium, 2018. ISBN 978-1-936213-19-1)
https://www.unicode.org/versions/Unicode11.0.0/
For references consulted particularly in designing the repertoire for the Armenian Script for the second level please see details in the Table of References below.
Reference [0] refers to the Unicode Standard version in which corresponding code points were initially encoded. Reference [100] corresponds to a source given in [Proposal-Armenian] for justifying the inclusion of for the corresponding code points. Single code points or ranges may have multiple source reference values.
Repertoire
Repertoire Summary
Number of elements in repertoire | 49 | ||||
---|---|---|---|---|---|
Number of code points for each script |
|
||||
Longest code point sequence | 1 |
Repertoire by Code Point
The following table lists the repertoire by code point (or code point sequence). The data in the Script and Name column are extracted from the Unicode character database. Where a comment in the original LGR is equal to the character name, it has been suppressed.
For any code point or sequence for which a variant is defined, additional information is provided in the Variants column. See also the legend provided below the table.
Code Point |
Glyph | Script | Name | Ref | Tags | Required Context | Variants | Comment |
---|---|---|---|---|---|---|---|---|
U+002D | - | Common | HYPHEN-MINUS | [0] | not: hyphen-minus-disallowed | ⍟ | ||
U+0030 | 0 | Common | DIGIT ZERO | [0] | Common-digit | ⍟ | ||
U+0031 | 1 | Common | DIGIT ONE | [0] | Common-digit | ⍟ | ||
U+0032 | 2 | Common | DIGIT TWO | [0] | Common-digit | ⍟ | ||
U+0033 | 3 | Common | DIGIT THREE | [0] | Common-digit | ⍟ | ||
U+0034 | 4 | Common | DIGIT FOUR | [0] | Common-digit | ⍟ | ||
U+0035 | 5 | Common | DIGIT FIVE | [0] | Common-digit | ⍟ | ||
U+0036 | 6 | Common | DIGIT SIX | [0] | Common-digit | ⍟ | ||
U+0037 | 7 | Common | DIGIT SEVEN | [0] | Common-digit | ⍟ | ||
U+0038 | 8 | Common | DIGIT EIGHT | [0] | Common-digit | ⍟ | ||
U+0039 | 9 | Common | DIGIT NINE | [0] | Common-digit | ⍟ | ||
U+0561 | ա | Armenian | ARMENIAN SMALL LETTER AYB | [0], [100] | Armenian | |||
U+0562 | բ | Armenian | ARMENIAN SMALL LETTER BEN | [0], [100] | Armenian | |||
U+0563 | գ | Armenian | ARMENIAN SMALL LETTER GIM | [0], [100] | Armenian | |||
U+0564 | դ | Armenian | ARMENIAN SMALL LETTER DA | [0], [100] | Armenian | |||
U+0565 | ե | Armenian | ARMENIAN SMALL LETTER ECH | [0], [100] | Armenian | |||
U+0566 | զ | Armenian | ARMENIAN SMALL LETTER ZA | [0], [100] | Armenian | |||
U+0567 | է | Armenian | ARMENIAN SMALL LETTER EH | [0], [100] | Armenian | |||
U+0568 | ը | Armenian | ARMENIAN SMALL LETTER ET | [0], [100] | Armenian | |||
U+0569 | թ | Armenian | ARMENIAN SMALL LETTER TO | [0], [100] | Armenian | |||
U+056A | ժ | Armenian | ARMENIAN SMALL LETTER ZHE | [0], [100] | Armenian | |||
U+056B | ի | Armenian | ARMENIAN SMALL LETTER INI | [0], [100] | Armenian | |||
U+056C | լ | Armenian | ARMENIAN SMALL LETTER LIWN | [0], [100] | Armenian | |||
U+056D | խ | Armenian | ARMENIAN SMALL LETTER XEH | [0], [100] | Armenian | |||
U+056E | ծ | Armenian | ARMENIAN SMALL LETTER CA | [0], [100] | Armenian | |||
U+056F | կ | Armenian | ARMENIAN SMALL LETTER KEN | [0], [100] | Armenian | |||
U+0570 | հ | Armenian | ARMENIAN SMALL LETTER HO | [0], [100] | Armenian | |||
U+0571 | ձ | Armenian | ARMENIAN SMALL LETTER JA | [0], [100] | Armenian | |||
U+0572 | ղ | Armenian | ARMENIAN SMALL LETTER GHAD | [0], [100] | set 1 | Armenian | ||
U+0573 | ճ | Armenian | ARMENIAN SMALL LETTER CHEH | [0], [100] | Armenian | |||
U+0574 | մ | Armenian | ARMENIAN SMALL LETTER MEN | [0], [100] | Armenian | |||
U+0575 | յ | Armenian | ARMENIAN SMALL LETTER YI | [0], [100] | Armenian | |||
U+0576 | ն | Armenian | ARMENIAN SMALL LETTER NOW | [0], [100] | Armenian | |||
U+0577 | շ | Armenian | ARMENIAN SMALL LETTER SHA | [0], [100] | Armenian | |||
U+0578 | ո | Armenian | ARMENIAN SMALL LETTER VO | [0], [100] | set 1 | Armenian | ||
U+0579 | չ | Armenian | ARMENIAN SMALL LETTER CHA | [0], [100] | Armenian | |||
U+057A | պ | Armenian | ARMENIAN SMALL LETTER PEH | [0], [100] | Armenian | |||
U+057B | ջ | Armenian | ARMENIAN SMALL LETTER JHEH | [0], [100] | Armenian | |||
U+057C | ռ | Armenian | ARMENIAN SMALL LETTER RA | [0], [100] | Armenian | |||
U+057D | ս | Armenian | ARMENIAN SMALL LETTER SEH | [0], [100] | Armenian | |||
U+057E | վ | Armenian | ARMENIAN SMALL LETTER VEW | [0], [100] | Armenian | |||
U+057F | տ | Armenian | ARMENIAN SMALL LETTER TIWN | [0], [100] | Armenian | |||
U+0580 | ր | Armenian | ARMENIAN SMALL LETTER REH | [0], [100] | Armenian | |||
U+0581 | ց | Armenian | ARMENIAN SMALL LETTER CO | [0], [100] | Armenian | |||
U+0582 | ւ | Armenian | ARMENIAN SMALL LETTER YIWN | [0], [100] | Armenian | |||
U+0583 | փ | Armenian | ARMENIAN SMALL LETTER PIWR | [0], [100] | Armenian | |||
U+0584 | ք | Armenian | ARMENIAN SMALL LETTER KEH | [0], [100] | Armenian | |||
U+0585 | օ | Armenian | ARMENIAN SMALL LETTER OH | [0], [100] | Armenian | |||
U+0586 | ֆ | Armenian | ARMENIAN SMALL LETTER FEH | [0], [100] | Armenian |
- Code Point
- A code point or code point sequence.
- Glyph
- The shape displayed depends on the fonts available to your browser.
- Script
- Shows the script property value from the Unicode Character Database. Combining marks may have the value Inherited and code points used with more than one script may have the value Common.
- Name
- Shows the character or sequence name from the Unicode Character Database.
- Ref
- Links to the references associated with the code point or sequence, if any.
- Tags
- LGR-defined tag values. Any tags matching the Unicode script property are suppressed in this view.
- Required Context
- Link to a rule defining the required context a code point or sequence must satisfy. If prefixed by “not:” identifies a context that must not occur.
- Variants
- Link to the variant set the code point or sequence is a member of, except where a coded point or sequence maps only to itself, in which case the type of that mapping is listed.
- Comment
- The comment as given in the XML file. However, if the comment for this row consists only of the code point or sequence name, it is suppressed in this view. By convention, comments starting with “=” denote an alias. If present, the symbol ⍟ marks a default item shared among a set of LGRs.
Variants
Variant Set Summary
Number of variant sets | 1 | |
---|---|---|
Largest variant set | 2 | |
Variants by Type |
|
Variant Sets
The following tables list all variant sets defined in this LGR, except for singleton sets. Each table lists all variant mapping pairs of the set; one per row. Mappings are assumed to be symmetric: each row documents both forward (→) and reverse (←) mapping directions. In each table, the mappings are sorted by Source value in ascending code point order; shading is used to group mappings from the same source code point or sequence.
Where the type of both forward and reverse mappings are the same, a single value is given in the Type column; otherwise the types for forward and reverse mappings, as well as comments and references, are listed above one another. For summary counts, both forward and reverse mappings are always counted separately.
In any LGR with variant specifications that are well behaved, all members within each variant set are defined as variants of each other; the mappings in each set are symmetric and transitive; and all variant sets are disjoint.
- Source
- By convention, the smaller of the two code points in a variant mapping pair.
- Target
- By convention, the larger of the two code points in a variant mapping pair.
- Glyph
- The shape displayed for source or target depends on the fonts available to your browser.
- → - forward
- Indicates that Type, Ref and Comment apply to the mapping from source to target.
- ← - reverse
- Indicates that Type, Ref and Comment apply to the reverse mapping from target to source.
- ↔ - both
- Indicates that Type, Ref and Comment apply to both forward and reverse mapping.
- Type
- The type of the variant mapping, including predefined variant types such as “allocatable” and “blocked”; or any that are defined specifically for this LGR.
- Ref
- One or more reference IDs (optional). A “/” separates references for reverse / forward mappings, if different.
- Comment
- A descriptive comment (optional). A “/” separates comments for reverse / forward mappings, if different.
Variant Set 1 — 2 Members
Source | Glyph | Target | Glyph | Type | Ref | Comment | |
---|---|---|---|---|---|---|---|
0572 | ղ | 0578 | ո | ↔ | blocked | Required if LGR is used with Common LGR |
Classes, Rules and Actions
Character Classes
Implicit (except script) | 1 |
---|---|
Implict defined by script tag | 2 |
The following table lists all named and implicit classes with their definition and a list of their members intersected with the current repertoire (for larger classes, this list is elided).
Name | Definition | Count | Members or Ranges | Ref | Comment |
---|---|---|---|---|---|
implicit | Tag=Common-digit | 10 | {0030-0039} | Any character tagged as Common-digit | |
implicit | Tag=sc:Armn | 38 | {0561-0586} | Any character tagged as Armenian | |
implicit | Tag=sc:Zyyy | 11 | {002D 0030-0039} | Any character tagged as Common |
- Members or Ranges
- Lists the members of the class as code points (xxx) or as ranges of code points (xxx-yyy). Any class too numerous to list in full is elided with "...".
- Tag=ttt
- A named or implicit class defined by all code points that share the given tag value (ttt).
- Implicit
- An anonymous class implicitly defined based on tag value and for which there is no named equivalent.
Whole label evaluation and context rules
Number of rules | 2 |
---|---|
Used to trigger actions | 1 |
Used as context rule (C) | 1 |
Anchored context rules | 1 |
The following table lists all named rules defined in the LGR and indicates whether they are used as trigger in an action or as context (when or not-when) for a code point or variant.
Name | Regular Expression | Used as Trigger |
Anchor | Used as Context |
Ref | Comment |
---|---|---|---|---|---|---|
leading-combining-mark | (start)[∅=[[∅=\p{gc=Mn}] ∪ [∅=\p{gc=Mc}]]] |
✔ | [150] | RFC 5891 restrictions on placement of combining marks ⍟ | ||
hyphen-minus-disallowed | (((start))← ⚓︎)|(⚓︎ →((end)))|(((start)..\u002D)← ⚓︎) |
✔ | C | [150] | RFC 5891 restrictions on placement of U+002D - ⍟ |
- Used as Trigger
- This rule triggers one of the actions listed below.
- Used as Context
- This rule defines a required or prohibited context for a code point C or variant V.
- Anchor
- This rule has a placeholder for the code point for which it is evaluated.
- Regular Expression
- A regular expression equivalent to the rule, shown in a modified notation as noted:
- ⚓︎ - context anchor
- Placeholder for the actual code point when a context is evaluated. The code point must occur at the position corresponding to the anchor. Rules containing an anchor cannot be used as triggers.
- (...)← - look-behind
- If present encloses required context preceding the anchor.
- →(..) - look-ahead
- If present encloses required context following the anchor.
- ( ) - group
- An anonymous nested rule is used to group match operators.
- (... | ...) - choice
- When there is more than one alternative in a rule, the choices are separated by the alternation operator (...|...).
- start or end
- (start) matches the start of the label; (end) matches the end of the label.
- . - any code point
- . matches any code point.
- [\p{ }] - property
- Set of all characters matching a given value for a Unicode property [\p{prop=val}]. Note: uppercase “\P” defines the complement of a property set.
- ∪, ∩, ∖, ∆ - set operators
- Sets may be combined by set operators (∪ = union, ∩ = intersection, ∖ = difference, ∆ = symmetric difference).
- ∅= - empty set
- Indicates that the following set is empty because of the result of set operations, or because none of its elements is part of the repertoire defined here. A rule with a non-optional empty set never matches.
- ⍟ - default rule
- Rules marked with ⍟ are included by default and may or may not be triggered by any possible label under this LGR.
Actions
The following table lists the actions that are used to assign dispositions to labels and variant labels based on the specified conditions. The order of actions defines their precedence: the first action triggered by a label is the one defining its disposition.
# | Condition | Rule / Variant Set | Disposition | Ref | Comment | |
---|---|---|---|---|---|---|
1 | if label matches | leading-combining-mark | → | invalid | labels with leading combining marks are invalid ⍟ | |
2 | if at least one variant is in | {out-of-repertoire-var} | → | invalid | any variant label with a code point out of repertoire is invalid ⍟ | |
3 | if at least one variant is in | {blocked} | → | blocked | any variant label containing blocked variants is blocked ⍟ | |
4 | if each variant is in | {allocatable} | → | allocatable | variant labels with all variants allocatable are allocatable ⍟ | |
5 | if any label (catch-all) | → | valid | catch all (default action) ⍟ |
- {...} - variant type set
- In the “Rule/Variant Set” column, the notation {...} means a set of variant types.
- ⍟ - default action
- Actions marked with ⍟ are included by default and may or may not be triggered by any possible label under this LGR.
Note: The following variant types are used in one or more actions, but are not defined in this LGR: allocatable, out-of-repertoire-var. This is not necessarily an error.
Table of References
The following lists the references cited for specific code points, variants, classes, rules or actions in this LGR. For General references refer to the References section in the Description.
[0] | The Unicode Standard, Version 1.1 Any code point originally encoded in Unicode 1.1 |
[100] | Omniglot, “Armenian (Հայերէն)”, https://www.omniglot.com/writing/armenian.htm |
[150] | RFC 5891, Internationalized Domain Names in Applications (IDNA): Protocol https://tools.ietf.org/html/rfc5891 |