Reference for Gittin 45:12

והאמר רבה בר בר חנה אמר רבי יוחנן ר"א היא אמוראי נינהו ואליבא דר' יוחנן:

<b><i>GEMARA</i></b>. We understand a deaf-mute, a lunatic, and a minor being disqualified, because they do not know what they are doing; also a heathen, because in any case he himself cannot release.<span class="x" onmousemove="('comment',' Since the Jewish law of marriage and divorce does not apply to him, and he cannot do on behalf of another what he cannot do on behalf of himself. ');">⁸</span>

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