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beamer / base / translator / dicts / translator-months-dictionary / translator-months-dictionary-French.dict

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\ProvidesDictionary{translator-month-dictionary}{French}

\providetranslation{January}{Janvier}
\providetranslation{February}{F\'evrier}
\providetranslation{March}{Mars}
\providetranslation{April}{Avril}
\providetranslation{May}{Mai}
\providetranslation{June}{Juin}
\providetranslation{July}{Juillet}
\providetranslation{August}{Ao\^ut}
\providetranslation{September}{Septembre}
\providetranslation{October}{Octobre}
\providetranslation{November}{Novembre}
\providetranslation{December}{D\'ecembre}