Reference for Chullin 100:10

אי זו היא כרס הפנימי סניא דיבי

Said R'Nahman B'Isaac, The rumen has fallen into the well.<span class="x" onmousemove="('comment',' I.e., the matter is far from clear, for R. Johanan has suggested some portion which he cannot identify or locate.');">⁵</span>

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