Reference for Bava Metzia 39:2
אביי אמר אפילו תימא ליתיה לדשמואל הכא במאי עסקינן בששטר כתובה יוצא מתחת ידה ורבא אמר אי משום שטר כתובה חיישינן לשתי כתובות
Raba, however, says that the production of the deed of the <i>Kethubah</i> makes no difference, for we apprehend that she may have had two copies of the <i>Kethubah</i>.<span class="x" onmousemove="('comment',' [One of which she disposed of by selling, and were it not for the fact that Samuel's ruling is accepted there would be good reason for not returning the receipt to the husband.] ');"><sup>4</sup></span> Abaye again says [in reply]: Firstly, we do not apprehend that she may have had two copies of the <i>Kethubah</i>, and secondly, a receipt has validity from its date.<span class="x" onmousemove="('comment',' I.e., from the date of writing, irrespective of the date of delivery, so that even if the debt had been sold in the interval the buyer has no claim, so that the Baraitha affords no support to Samuel's ruling. ');"><sup>5</sup></span> This is consistent with Abaye's view, for he says: 'The witnesses acquire it for him by their signatures.'<span class="x" onmousemove="('comment',' V. supra 13a; 19a. Cf. infra 35b. ');"><sup>6</sup></span>