Leviticus 18:23
"Neither shalt thou lie with any beast to defile thyself therewith: neither shall any woman stand before a beast to lie down thereto: it is confusion."
Cross References (ranked by relevance)
Exodus 22:19
Whosoever lieth with a beast shall surely be put to death.
Leviticus 20:12
And if a man lie with his daughter in law, both of them shall surely be put to death: they have wrought confusion; their blood shall be upon them.
Deuteronomy 27:21
Cursed be he that lieth with any manner of beast. And all the people shall say, Amen.