Leviticus 1:3

If his offering be a burnt sacrifice of the herd, let him offer a male without blemish: he shall offer it of his own voluntary will at the door of the tabernacle of the congregation before the LORD.

If his offering is a burnt offering from the herd, he shall offer a male without defect; he shall offer it [omit] at the doorway of the tent of meeting, so that he may be accepted before the LORD.