Reference for Chullin 243:34

מר סבר

Now those who refer this [dictum of Ulla's] to the first clause will certainly refer it to the later cause,<span class="x" onmousemove="('comment',' For since the skin was tanned and its character thus altered, there would be no other reason why it should remain unclean, except this precautionary measure stated by Ulla.');">¹⁸</span>

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