Template:Citation Style documentation/language
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- language: The language in which the source is written, if not English. Displays in parentheses with "in" before the language name or names. Use the full language name or ISO 639-1 code. When the source uses more than one language, list them individually separated by commas. Language names or language codes recognized by Wikimedia adds the page to the appropriate subcategory of Category:CS1 foreign language sources; do not use templates or wikilinks.