Reference for Bava Batra 204:1

רב שישא בריה דרב אידי אמר לעולם ר"ש היא והב"ע בניפלי

R. Shisha b. R. Idi said: It<span class="x" onmousemove="('comment',' The final clause of the Mishnah of Ohaloth requiring a search along a distance of twenty cubits. ');">¹</span> may, in fact, be in accordance with the view of R. Simeon,<span class="x" onmousemove="('comment',' Who requires the area of a grotto for adults to be six by eight. ');">²</span>

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