Reference for Nedarim 94:3

אמר רבא דילמא לכתחילה הוא דלא ואי עבד עבד

Said Raba, possibly it is forbidden [to make an exchange] in the first place only, but if it has been done, it is valid.<span class="x" onmousemove="('comment',' I.e., it can be maintained that the problem regarding what is exchanged for them, is whether one may deliberately exchange these fruits for something else, so that it shall be permitted to the muddar. But if they were exchanged, they certainly are permitted. Hence, in this case, since the wife receives the money before the creditors exact it from her husband, it is regarded as a fail accompli, the legality of which is not in doubt. (The explanation follows Asheri. Ran gives a different interpretation). ');">³</span>

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