Reference for Chullin 164:49

אילימא בזה אחר זה ובשתי התראות מ"ט דרבי יהודה

if one after the other, he is not liable.<span class="x" onmousemove="('comment',' For the warning at each striking is a dubious one and R. Judah is of the opinion that such is no warning.');">²³</span>

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