Reference for Niddah 119:16

רבי מאיר אומר

experienced a discharge once before; and R. Meir said, If she is capable of a menstrual discharge even though she never yet experienced one.<span class="x" onmousemove="('comment',' Similarly the Baraitha cited by Raba is to be explained that the first Tanna holds that 'she may not attribute it to the gentile woman' unless the latter had experienced a discharge once before, while R. Meir maintains that it may be attributed to her even if she is only capable of a discharge, though she had not experienced one. Both Baraithas thus give the same rulings in different words, and Rab's view is upheld by that of the first Tanna in each. ');">¹⁴</span>

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