Reference for Niddah 141:18

אלא הא דתנן ב"ש אומרים

out of a deference to the living menstruants. Formerly they were wont to subject to ritual immersion utensils used by dying zabs,<span class="x" onmousemove="('comment',' V. p. 492, n. 12. ');">¹⁶</span>

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