Reference for Bava Batra 345:5

דאיתמר אותיות נקנות במסירה אביי אמר צריך להביא ראיה ורבא אמר אינו צריך להביא ראיה

Our Tanna<span class="x" onmousemove="('comment',' The author of our Mishnah. ');">¹³</span> 'holds that proof need not be produced<span class="x" onmousemove="('comment',' The possession of the bond is sufficient evidence that the debt is owing to its holder. Hence the inference from our Mishnah, that one of the Josephs may present a bond of indebtedness against a third person who cannot consequently refuse payment by demanding additional proof of the holder's title to ownership. ');">¹⁴</span> while the external Tanna<span class="x" onmousemove="('comment',' The author of the Baraitha. ');">¹⁵</span>

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