Rashi on Leviticus 11:39/רש"י על ויקרא י״א:ל״ט

1בנבלתה [HE THAT TOUCHETH] THE CARRION THEREOF [SHALL BE UNCLEAN] — but not if he touches the bones and sinews, nor the horns and claws, and not the hide after these have been removed from the body (Sifra, Shemini, Section 10 5; Chullin 117b).