Reference for Bekhorot 52:32

נולד לו מום בתוך שנתו רשאי לקיימו כל שנים עשר חדש

and that which comes later in the first text<span class="x" onmousemove="('comment',' 'The first-born of thy sons' we link up with the text 'Likewise thou shalt do with thy sheep'.');">¹⁹</span>

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