specified by Iso639Language.\r
@param Iso639Language If TRUE, then all language codes are assumed to be\r
in ISO 639-2 format. If FALSE, then all language\r
codes are assumed to be in RFC 4646 language format.\r
\r
@retval NULL The best matching language could not be found in SupportedLanguages.\r
specified by Iso639Language.\r
@param Iso639Language If TRUE, then all language codes are assumed to be\r
in ISO 639-2 format. If FALSE, then all language\r
codes are assumed to be in RFC 4646 language format.\r
\r
@retval NULL The best matching language could not be found in SupportedLanguages.\r