Reference for Niddah 59:3

כגון שבאת לפנינו בין השמשות דיהבינן לה טבילה יתירתא

Sixty-six.<span class="x" onmousemove="('comment',' So that during the presumed days of cleanness no more than sixty-six immersions can be expected owing to the presumption that each might possibly be the eightieth day. ');">³</span>

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