Reference for Bekhorot 51:23

ואתא ר' יוסי למימר

For the first Tanna [quoted above] holds that the difference of opinion between Akabya and the Sages refers to a dead firstling and the same applies in the case where he slaughtered it,<span class="x" onmousemove="('comment',' Since we do not find it stated by the first Tanna quoted above, that where he slaughtered it all maintain that the wool is allowed to be used.');">¹³</span>

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