Reference for Niddah 71:35

הלכתא כוותיה דרב בין לקולא בין לחומרא

told us, 'Mar Zutra once visited our place when he delivered a discourse In which he laid down: The law is to be restricted in agreement with Rab<span class="x" onmousemove="('comment',' That if the discharge was continuous from within the clean period into the unclean one following, it conveys uncleanness as if it had emanated from an unclean source. ');">³¹</span>

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