Reference for Bava Batra 326:6

וליחוש דלמא כתב הוא ועדיו בשיטה אחת ואמר אנא לרבות בעדים הוא דעבדי

But is [there no reason] to apprehend that the text and the witnesses might be written in one line<span class="x" onmousemove="('comment',' I.e., all the Original text of the deed would be cut away, leaving only the two lines' blank space above the signatures and, on one of these, a forged text and signatures would be written. ');">¹⁴</span> and [the holder of the deed might] plead, 'I did this<span class="x" onmousemove="('comment',' Arranged for signatures of witnesses in more than one line. ');">¹⁵</span> in order to increase the number of witnesses'?<span class="x" onmousemove="('comment',' The genuine witnesses, though appearing in the second line, would not invalidate the deed, since the first line contains the text and witnesses, while for confirmation of the deed, the holder would not make use of the signatures of the fictitious witnesses in the first line but of those of the genuine witnesses in the second line. ');">¹⁶</span>

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