Reference for Bava Metzia 100:3

תפשוט דבטול מקח לרבנן לעולם חוזר דכיון דאמר להו רבי טרפון הויא אונאה שמחו כי אמר להו כל היום חזרו

whilst they reverted [to the ruling of the Rabbis] when he told them [that the time for withdrawing is] all day. For if you should think that in the view of the Rabbis the annulment of the sale<span class="x" onmousemove="('comment',' For an overcharge of more than a sixth. ');">³</span>

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