Reference for Yevamot 139:3
ומה התם דלהאי איסורא ולהאי איסורא בתריה דידיה שדינן ליה הכא דלהאי איסורא ולהאי היתירא לא כל שכן
here<span class="x" onmousemove="('comment',' The case of the betrothed. ');"><sup>7</sup></span> where she is forbidden to any other man and is permitted to him.<span class="x" onmousemove="('comment',' The man who betrothed her. ');"><sup>8</sup></span> Said Abaye to him: It may still be maintained that Rab is of the opinion that wherever she is suspected of illicit relations with strangers the child is deemed to be a bastard even if she is also suspected of such relations with him; and our Mishnah deals with one who had not been suspected at all.<span class="x" onmousemove="('comment',' Either in respect of the violator or seducer on the one hand or in respect of any others. All that our Mishnah teaches is that if cohabitation with the former took place, even if only once, the child is regarded as his. ');"><sup>9</sup></span>