Reference for Zevachim 225:8

ורבי אושעיא אמר כשרה (במדבר יט, ה) על פרשה ישרף מקום שפורשת למיתה שם תהא שריפתה

Resh Lakish said: It is fit, [because it says, and she s be brought forth'] without the camp and he shall slay.<span class="x" onmousemove="('comment',' Which implies anywhere outside the camp.');">¹¹</span> And it was stated likewise:)<span class="x" onmousemove="('comment',' Sh.M. deletes the bracketed passage.');">¹²</span>

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