https://github.com/citation-style-language/locales/ is the official repository for Citation Style Language (CSL) locale files.
Locale files for CSL 1.0 and CSL 0.8.1 are stored in the "master" and "b0.8" branches, respectively.
For more information, see https://github.com/citation-style-language/locales/wiki and CitationStyles.org.