Reference for Chullin 135:35

בהמה המקשה לילד הוציא עובר את ידו והחזירה ואחר כך שחט את אמו מותר באכילה

If it put forth its fore-limb and it was immediately cut off, and th the dam was slaughtered, that which is outside<span class="x" onmousemove="('comment',' I.e., the limb that had been cut off.');">¹⁹</span>

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