Reference for Yevamot 76:6

אמר ליה רבה אדמפלגי בגופה ולאחר מיתה לפלגו בחייה ולפירות

while they are only doubtful possessors, and doubt cannot override a certainty.<span class="x" onmousemove="('comment',' Hence Beth Shammai as well as Beth Hillel agree that she is fully entitled to sell the property or to give it away. ');">¹¹</span> In the final clause, however, where she is dead, both groups come equally as heirs<span class="x" onmousemove="('comment',' Lit., 'those come to inherit' (bis). Had the levirate bond borne the same force as marriage the estate would undoubtedly have become the property of the levir only. Had it not borne the same force as marriage the estate would have been given to her father's heirs only, and the levir would have had no claim whatsoever. The claims of either group are consequently evenly balanced. ');">¹²</span>

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