Reference for Chullin 59:31

מתיב רבי אלעזר

But when I reported this statement to Samuel he said to me, "We must have a wide open cut<span class="x" onmousemove="('comment',' Since the organs of the throat are tightened in preparation for the slaughtering, if they are cut in one place there will be a wide open cut, but if cut in several places none of the cuts will open wide; hence the slaughtering is invalid (Rashi) . Accordingly a wide open cut is synonymous with a single cut. V. however Tosaf ad loc. for other interpretations. yuja .j');">²¹</span>

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