Referenced in our Library 9 places Mishnah מִשְׁנָהPirkei Avot 5Talmud Bavli תַּלְמוּד בַּבְלִיArakhin 13bBava Kamma 27bBava Kamma 28aBekhorot 12aEruvin 27bKiddushin 10bMenachot 49b ×2Pesachim 96a