Leviticus 5:7-10
And if he be not able to bring a lamb, then he shall bring for his trespass, which he has committed, two turtledoves, or two young pigeons, to the LORD; one for a sin offering, and the other for a burnt offering.
Nave's Topical Index—AKJV

Leviticus 12:8
And if she be not able to bring a lamb, then she shall bring two turtles, or two young pigeons; the one for the burnt offering, and the other for a sin offering: and the priest shall make an atonement for her, and she shall be clean.
Nave's Topical Index—AKJV