Reference for Niddah 127:45

תניא כותיה דרב פפא

was said only in regard to the establishment of a settled period,<span class="x" onmousemove="('comment',' Sc. that the uncleanness should begin just at the time of the period and not earlier; and that the settled period should not be abolished unless a change occurred three times. ');">⁴¹</span>

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