Reference for Niddah 115:9

על עקבה ועל ראש גודלה טמאה וכו'

There is no question [that the woman is clean where she sat on] a cloak since it cannot be thoroughly examined and one may, therefore, well assume [that the stain] emanated from an external source,<span class="x" onmousemove="('comment',' Before the woman sat on it. ');">⁹</span>

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