Reference for Chullin 148:12

ר' יהודה אומר

And R'Eleazar had said in the name of R'Oshaia that their dispute referred to a living nine months' foetus, R'Meir ruling according to his principle<span class="x" onmousemove="('comment',' That a living nine months' foetus is deemed an animal proper and must itself be slaughtered.');">⁴</span>

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