Reference for Yevamot 73:5

איתמר קדשה בתוך שלשה וברח פליגי בה רב אחא ורפרם חד אמר משמתינן ליה וחד אמר עירוקיה מסתייה הוה עובדא ואמר להו רפרם עירוקיה מסתייה:

Here,<span class="x" onmousemove="('comment',' Where the levir married his sister-in-law while she was an expectant, or nursing mother. ');">¹⁴</span> however, in accordance with whose view could we act? If in accordance with that of R. Meir, he surely stated that he<span class="x" onmousemove="('comment',' The levir. ');">¹⁵</span> must put her out and never remarry her! And if in accordance with the view of the Rabbis, they, surely, stated [that she must be sent away] by means of a letter of divorce!<span class="x" onmousemove="('comment',' V. supra 36b and cf. p. 229, nn. 16 and 17. ');">¹⁶</span>

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