Reference for Chullin 32:11

דלמא פרושי קא מפרש לה

Said R''Anan in the name of Samuel: This is the law provided the knife was on top and the throat of the animal below.<span class="x" onmousemove="('comment',' And the slaughterer moved the head to and fro across the knife.');">⁶</span>

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