Reference for Bava Batra 345:7

ורבא אמר שאני אחין דשמטו מהדדי

and Raba said: He need not produce proof.<span class="x" onmousemove="('comment',' Cf. supra note 4. ');">¹⁹</span> Said Abaye: Whence do I derive this?<span class="x" onmousemove="('comment',' That proof is required apart from the production of the deed. ');">²⁰</span> — For it was taught: 'The brother<span class="x" onmousemove="('comment',' Lit., 'one of the brothers'. ');">²¹</span>

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