Reference for Bava Batra 261:2

בעי רבא בבריא היאך כי קא"ר יוחנן בן ברוקה בשכ"מ דבר אורותי הוא אבל בבריא לא או דלמא אפילו בבריא נמי

[is the law in the case of] a person in good health?<span class="x" onmousemove="('comment',' Who appointed one of his legal heirs to inherit all his estate. ');">³</span> Does R. Johanan b. Beroka<span class="x" onmousemove="('comment',' In our Mishnah, supra 130a. ');">⁴</span> speak [only] of [the case of] a dying man, who has the right to appoint an heir [on the spot],<span class="x" onmousemove="('comment',' Without the necessity for a formal written document. The instructions of a dying man, though only verbal, are legally binding. ');">⁵</span>

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