Reference for Bekhorot 52:13

כל שעיקרו הפוך כלפי ראשו

<big><b>MISHNAH: </b></big>UP TO HOW LONG IS AN ISRAELITE BOUND TO ATTEND TO A FIRSTLING?<span class="x" onmousemove="('comment',' In our days, after the destruction of the Temple, for what length of time must the Israelite care for and feed the animal perforce the priest claims it?');">⁷</span>

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