Reference for Shevuot 35:7

אמר ליה רבינא לרב אדא מי מצית לאוקמה לההיא בשלא סמוך לוסתה ואפרישה והא נמצא קתני ונמצא לבתר הכי משמע ואי אפרישה מעיקרא כי פריש ליה מעיקרא הויא ליה ידיעה

they are [both] unclean because of the doubt,<span class="x" onmousemove="('comment',' The woman is definitely unclean, because she is now menstruous, but the man is unclean only because of the doubt whether he had cohabited with her when she was already unclean, or before her uncleanness commenced.');">¹⁴</span> but exempt from bringing a sacrifice.<span class="x" onmousemove="('comment',' Because she may have become unclean infer cohabitation; and he does not even bring a suspensive guilt offering for the doubtful sin');">¹⁵</span> And because he wishes to teach us [this law concerning] 'If found on hers',<span class="x" onmousemove="('comment',' And to distinguish between the case where she applied her rag immediately and the case where an interval elapsed (v. Nid. 14a) .');">¹⁶</span>

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