Related for Rosh Hashanah 38:12

מאי שנא ל' דידעי חדש נמי ידעי א"ר פפא מ"ד חדש רצה חדש רצה שלשים

- No. Both hold that the ceremonies observed in the second are not observed in the first, and here they differ on the question of the prolongation of the year,<span class="x" onmousemove="('comment',' I.e., the [days of the month of the first Adar which is inserted to prolong the year (Rashi) .');">⁹</span>

Tosefta Rosh Hashanah (Lieberman)