Reference for Bava Batra 320:2

ואיפוך אנא מתוך שנתרבה בקשריו נתרבה בעדיו

the folded [one]; <i>and procure the evidence</i>, [implies] two [witnesses]<span class="x" onmousemove="('comment',' The minimum number of witnesses. All evidence must be given by no less than two witnesses unless the contrary has been specifically indicated. (V. Sot. 2b). ');">³</span> witnesses, [implies] three.<span class="x" onmousemove="('comment',' The minimum number above two that has already been mentioned. ');">⁴</span> How [is] this<span class="x" onmousemove="('comment',' That two, as well as three witnesses are required. ');">⁵</span>

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