Reference for Niddah 3:12

מטמאה מעת לעת אינה מונה אלא משעה שראתה

LIKE AN EXAMINATION WHICH LESSENS EITHER THE PERIOD OF THE [PAST] TWENTY-FOUR HOURS OR THE PERIOD FROM THE [PREVIOUS] EXAMINATION TO THE [LAST] EXAMINATION. HOW [IS ONE TO UNDERSTAND THE RULING THAT]<span class="x" onmousemove="('comment',' In the case of 'ANY WOMAN WHO HAS A SETTLED PERIOD (supra). ');">¹¹</span>

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