Reference for Niddah 95:43

ורבי מאיר לטעמיה דחייש למיעוטא ורבנן לטעמייהו דלא חיישי למיעוטא

— If 'THOUGH THIS IS IMPOSSIBLE had not been stated, It might have been presumed that in most women the lower mark appears first and in that of a minority the upper mark appears first, and that R. Meir<span class="x" onmousemove="('comment',' In regarding the girl as a minor. ');">³⁷</span>

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