Reference for Niddah 50:10

א"ר נחמן אמר רבה בר אבוה ל"ש אלא מלמטה למעלה אבל מן הצדדין אימא

two thighs are like two silk threads', and in connection with this R. Amram explained: Like those of the woof;<span class="x" onmousemove="('comment',' The threads of the woof are thicker than those of the warp. ');">⁹</span>

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