Reference for Chullin 225:19

בישרא דמנח נפקותא)

- Not at all; but since in the preceding clause it teaches of the case where the clean fish was salted, and the unclean was not, it teaches also in the second clause of the case where the unclean fish was salted and the clean was not.<span class="x" onmousemove="('comment',' Actually even if both were salted the clean fish would be forbidden.');">⁷</span>

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