Translation:Talmud, Seder MoedTractate Rosh Hashana…
“ If a king ascended the throne on the twenty-ninth of Adar, as soon as the first of Nisan arrives17 he is reckoned to have reigned a year. If on the other hand he ascended the throne on the first of Nisan, he is not reckoned to have reigned a year till the next first of Nisan comes round. ”
