Reference for Keritot 29:11

חייב אחת על כולן או חייב על כל אחת ואחת

For R'Abbahu said in the name of R'Johanan: In the expression, They are near kinswomen; it is wickedness,<span class="x" onmousemove="('comment',' Lev. XVIII, 17. is in the singular, to indicate that even if several inter-relations are combined in one woman she is still a kinswoman singly, and subject to one sacrifice only.');">⁵</span>

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