Reference for Bekhorot 58:1

ורב יהודה בר אמי משמיה דרב יהודה אמר

And R'Judah B'Ami reported in the name of Rab Judah: A beth ha-peras which has been trodden is levitically clean.<span class="x" onmousemove="('comment',' The field having been trodden by several people, it is impossible that a dead man's bone the size of a barley-corn could remain to cause uncleanness, v. Pes. 92b.');">¹</span>

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