Reference for Niddah 138:14

<big><strong>מתני׳</strong></big> הזב והזבה והנדה והיולדת והמצורע שמתו מטמאין במשא עד שימוק הבשר

Said R. Aha son of R. Joseph to R. Ashi, Have we not had recourse to explanations of this ruling?<span class="x" onmousemove="('comment',' We had; since in the absence of explanations it bristles with difficulties, ');">¹³</span>

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