Midrasz do Kapłańska 4:28

1 (Vayikra 4:28): "If his sin becomes known to him (wherein he sinned"): And not if others tell him. I might think even if he does not refute (them); it is, therefore, written (to negate this): "if it becomes known."

4) I might think that he does not fulfill his obligation with his father's offering, even with monies that his father separated, and even from the lesser to the lesser or the greater to the greater — but that he does fulfill it with an offering that he separated for himself, even from the greater to the lesser or the lesser to the greater. It is, therefore, written: (Vayikra 4:28): "his offering … for his sin" — It must be (separated) for that sin.

9) (Vayikra 4:32): "And if a lamb he brings as his offering for a sin-offering": R. Shimon says: "Lambs" precede "goats" in all other places. I might think this is so because they are preferred to them. It is, therefore, written: "If a lamb he brings as an offering for his sin-offering" (after "goats" [Vayikra 4:28]), to teach that they are equivalent.