Reference for Niddah 58:8

יולדת נקבה בזוב היא אלא שבוע רביעי אע"ג דקא חזיא דם תשמש דהא דם טהור

she may perform her marital duty on the night preceding the thirty-fifth day<span class="x" onmousemove="('comment',' Of her arrival, viz., the last night of the fifth week. After that night, however, as will be explained presently, no cohabitation can be allowed. ');">⁸</span>

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