Reference for Niddah 118:58

ישבו על ספסל של אבן או על האיצטבא של מרחץ רבי נחמיה מטהר

or is it possible that there is no difference? — Come and hear: Since R. Simeon ruled, THE PRESUMPTION IS THAT BLOOD ISSUES FROM THE WOMAN,<span class="x" onmousemove="('comment',' Which clearly indicates that he never attributes it to the man. ');">⁵²</span>

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