Reference for Bava Batra 349:9

בתר דבעיא הדר פשטה אין אדם משטה בשעת מיתה ודברי שכ"מ ככתובין וכמסורין דמו:

might jest in the hour of his death or that a man does not jest in the hour of his death? Is it necessary [for him] to say. 'Write',<span class="x" onmousemove="('comment',' I.e., a bond. In the case of a pots in in good health such an order is essential to the validity of the creditor's claim (cf. supra 40a). ');">²²</span> or is it not necessary to say, 'Write'? — After having raised these questions, he answered them himself:<span class="x" onmousemove="('comment',' Lit., 'after he enquired he returned and solved it'. ');">²³</span> No one jests in the hour of [his] death, and the words of a dying man are regarded [legally] as written and delivered.<span class="x" onmousemove="('comment',' Hence there is no need to add, 'Be my witnesses', or, 'Write out a bond'. ');">²⁴</span>

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