Reference for Niddah 131:11

מאי בינייהו

R. Simeon b. Gamaliel ruled: The blood of a wound that is discharged through the source is unclean. Our Masters, however, testified that the blood of a wound that is discharged through the source is clean. What is the point at issue between them?<span class="x" onmousemove="('comment',' Rabbi and our Masters on the one hand and R. Simeon on the other. ');">⁸</span>

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