Reference for Bava Metzia 80:2

והאמר שמואל המשתכר אל ישתכר יותר על שתות

But Samuel said: He who profits must not profit more than a sixth?<span class="x" onmousemove="('comment',' Yet 1/6 th is permissible: why then did Rab Judah content himself with 1/12 th? ');">²</span>

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