Reference for Niddah 127:44

מהו דתימא חדא לחד תרי לתרתי ותלתא לתלתא קא משמע לן

FOR A WOMAN MAY NOT REGARD HER MENSTRUAL PERIOD AS SETTLED UNLESS THE RECURRENCE HAS BEEN REGULAR etc. R. Papa explained: This<span class="x" onmousemove="('comment',' That the occurrence must be repeated three times. ');">⁴⁰</span>

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