Reference for Sotah 60:5

ומר סבר שני עושה שלישי בחולין

holds that a second degree of defilement does not create a third with the non-holy,<span class="x" onmousemove="('comment',' [For this reason he allows in the second teaching a quantity of the size of an egg; and the reservation in the first teaching is merely as a precaution lest the piece of dough may come in contact with impure dough after the hallah has been designated.] ');">⁵</span>

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