Numbers 29:19

And one kid of the goats for a sin offering; beside the continual burnt offering, and the meat offering thereof, and their drink offerings.

Cross-reference

Numbers 29:22 repeats the same sin offering goat for the second day of Tabernacles, identical to this verse.

Numbers 29:25 continues the pattern with one male goat for a sin offering on the third day, mirroring this verse.

Leviticus 4:23 also prescribes a male goat for a sin offering, but for an individual's guilt, not the communal feast offering here.