Reference for Niddah 56:8

לא הא מני ר' אליעזר היא

And when it was asked, 'What is the practical difference between them?'<span class="x" onmousemove="('comment',' R. Eliezer and R. Akiba. ');">¹³</span> Hezekiah replied: The practical difference between them is [the case of a man who is uncertain whether he touched] a dead creeping thing or the carcass of a beast, R. Eliezer<span class="x" onmousemove="('comment',' Who explicitly mentioned 'unclean swarming thing'. ');">¹⁴</span>

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