Reference for Bava Batra 189:8

מרתף של יין וכו': היכי דמי אי דא"ל מרתף של יין סתם קשיא אי דאמר ליה מרתף זה של יין קשיא

] What a comparison! There,<span class="x" onmousemove="('comment',' In the case of the overcharge. ');">¹⁴</span> one spoke to the other of equal values<span class="x" onmousemove="('comment',' The price. according to the original arrangement, had to be equal to the value of the produce. The buyer. therefore, had a right to claim the return of an overcharge, even if it were less than a sixth. ');">¹⁵</span>

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