Reference for Niddah 75:26

מאי קמ"ל

preceding the period of her menstruation,<span class="x" onmousemove="('comment',' As zibah is not established unless a discharge appeared on three consecutive days in the zibah period, and as the third day was already one of the menstruation period, none of the days can be counted as one of a major zibah. ');">²³</span>

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