Reference for Bava Metzia 9:15

אמר ליה אביי אם איתא משתבע והא גזלן הוא א"ל שכנגדו קאמינא

If the plaintiff claims wheat, and the defendant admits barley, the defendant is free [from taking an oath], but Rabban Gamaliel obliges [the defendant to take an oath].<span class="x" onmousemove="('comment',' If the claim is for wheat, and the admission is for barley, it is not considered a 'partial admission' and does not involve an oath. ');">¹⁴</span>

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