Appendix 3. Declare the language of the metadata (xml:lang attribute): Implementation examples following metadata standards/guidelines

Datacite Schema 4.4xml:lang=”EN”, for example <xs:element name=”title” maxOccurs=”unbounded”><xs:annotation><xs:documentation>A name or title by which a resource is known.</xs:documentation></xs:annotation><xs:complexType><xs:simpleContent><xs:extension base=”xs:string”><xs:attribute name=”titleType” type=”titleType” use=”optional”/><xs:attribute ref=”xml:lang”/>Similarly, for xs:element name=”creatorName“>, <xs:element name=”publisher“>, <xs:element name=”subjects” minOccurs=”0″>, <xs:element name=”contributorName“>, <xs:element name=”rightsList” minOccurs=”0″>, <xs:element name=”descriptions” minOccurs=”0″>, <xs:element name=”language” type=”xs:language” minOccurs=”0″>, <xs:annotation><xs:documentation>Primary language of the resource. Allowed values are taken from IETF BCP 47, ISO 639-1 language codes.</xs:documentation>
Dublin Core (DC)Where the language of the value is indicated, it should be encoded using the ‘xml:lang’ attribute. For example:<dc:subject xml:lang=”en”>seafood</dc:subject><dc:subject xml:lang=”fr”>fruits de mer</dc:subject>
Electronic thesis and dissertation metadata standard (ETDMS)Language is a global qualifier that can be used in any element: https://ndltd.org/wp-content/uploads/2021/04/etd-ms-v1.1.html#qualifiers 
Metadata Object Description Schema (MODS)There are Language-Related Attributes https://www.loc.gov/standards/mods/userguide/attributes.html#listISO 639-2/b 
OpenAIRE institutional and thematic repository GuidelinesThe use of the xml:lang attribute to indicate the language of the metadata. Example: <dc:description>  Foreword [by] Hazel Anderson; Introduction; The scientific heresy:  transformation of a society; Consciousness as causal reality [etc]</dc:description>
<dc:description xml:lang=”en-US”>  A number of problems in quantum state and system identification are  addressed.</dc:description>OpenAIRE supports the xml language tag and the aggregator conducts metadata checks for language – e.g. in subjects, titles and abstracts/descriptions; no names though – ORCID is recommended for names – OpenAIRE I+T: Title https://openaire-guidelines-for-literature-repository-managers.readthedocs.io/en/latest/field_title.html#dci-title , Description  https://openaire-guidelines-for-literature-repository-managers.readthedocs.io/en/latest/field_description.html#attribute-lang-oOpenAIRE also allows multiple languages https://openaire-guidelines-for-literature-repository-managers.readthedocs.io/en/v4.0.0/field_language.html – content resource has this language.
JPCOAR 1.0.2https://schema.irdb.nii.ac.jp/ja/schemaxml:lang attribute can be used for each element In principle, use the two-digit language code of ISO 639-1 (e.g. Japanese: “ja”; English: “en”).For Japanese ‘yomi’, use “ja-Kana“. Where ‘yomi’ is entered, you must enter its original information (i.e. in kanji) with the description that ‘xml:lang is “ja”’.For Chinese, it is desirable to separately enter simplified Chinese as “zh-ch” and traditional Chinese as “zh-tw”.
JPCOAR Metadata Schema 2.0 Drafthttps://schema.irdb.nii.ac.jp/ja/schema/2.0-draft/14 https://schema.irdb.nii.ac.jp/ja/schema/2.0-draft/1 Change from 1.0.2 : additionally support “ja-Latn”.The Excerpts from updated part:For Japanese ‘yomi’with Katakana characters, use “ja-Kana” and For Japanese ‘yomi’ with Roman letters (alphabet), use “ja-Latn”.  Where ‘yomi’ is entered, you must enter its original information (i.e. in kanji) with the description that ‘xml:lang is “ja”’.
Akdeniz, Esra, & Moilanen, Katja. (2023). CMM CESSDA Metadata Model (3.0). Zenodo. https://doi.org/10.5281/zenodo.7528240 Language of Study TitleThe language of the content of the element.MISO 639-1Occurrence 1ddi:DDIInstance/s:StudyUnit/r:Citation/r:Title/r:String/@xml:lang Similarly for Language of Subtitle; Language of Alternative Title; Language of Versioning Reason; Language of Abstract; Language of Study Topic (descriptive); Language of Keyword (descriptive);  Language of discipline (freetext);  Language of Type of Data Source (descriptive); Language of Mode of Data Collection (descriptive); Language of Data Access Conditions; Language of Metadata Access Conditions (Study); Language of Full Name of Organization; Language of Organization Name Abbreviation/Acronym; Language of Description of the organization; Language of Dataset Version Description; Dataset Language; Language of Dataset File Description; Language of File Name; Language of Document Title; Language of Publication Title; Language of Name of the Journal/Serial – 75 metadata fields overall to indicate the language; There are also metadata fields to indicating translations, e.g. Status of Study TitleIs the content of the element translated?Rtrue, falseOccurrence 0-1ddi:DDIInstance/s:StudyUnit/r:Citation/r:Title/r:String/@isTranslated; and 28 metadata fields mentioning translation

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