Reference for Yevamot 76:18

ולותביה כתובה דמתניתין

and that they need not drink,<span class="x" onmousemove="('comment',' The water of bitterness. V. Num. V, 24. ');">³³</span> and Beth Hillel rule that they either drink<span class="x" onmousemove="('comment',' The water of bitterness. V. Num. V, 24. ');">³³</span>

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