Reference for Bava Kamma 224:9
אמר רבא הלכתא מקיימין את השטר שלא בפני בעל דין ואפי' עומד וצווח ואי אמר נקיטו לי זימנא עד דמייתינא סהדי ומרענא ליה לשטרא נקטינן ליה אי אתא אתא אי לא אתא נטרינן ליה בה"ב
even not in the presence of the other party [to the suit], whereas R. Johanan said that a document cannot be authenticated in the absence of the other party to the suit. R. Shesheth said to R. Joseph b. Abbahu: I will explain to you the reason of R. Johanan. Scripture says: And it hath been testified to its owner and he hath not kept him in;<span class="x" onmousemove="('comment',' Ex. XXI, 29. ');"><sup>14</sup></span> the Torah thus lays down that the owner of the ox has to appear and stand by his ox [when testimony has to be borne against it]. But Raba said: The law is that a document may be authenticated even not in the presence of the other party; and even if he protests aloud before us [that the document is a forgery]. If, however, he says, 'Give me time till I can bring witnesses, and I will invalidate the document', we have to give him time.<span class="x" onmousemove="('comment',' As a rule for thirty days; cf. B.M. 118a. ');"><sup>15</sup></span>