Reference for Niddah 71:18

ותטמא מפקידה לפקידה

it suffices for her to reckon her uncleanness from the time of her observation,<span class="x" onmousemove="('comment',' Which (cf. prev. n.) is rightly regarded as a first discharge after many days from the unclean source. A first discharge in the case of a nursing-woman, as in that of another three categories of woman, does not cause any retrospective uncleanness. ');">¹⁶</span>

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