Chabad.org — English translation + Rashi
Torah Temimah points to Toras Kohanim (Sifra) on 3:7.
Sefaria — Sifra / Toras Kohanim
English: “And he shall bring it before Hashem” — to include the semichah.
Ribbuy of semichah — the bringing before Hashem includes the requirement of laying hands.
The bringing before Hashem includes the requirement of laying hands. The Sifra treats the language of presentation as encompassing the act of semichah that must accompany the offering. The result is that the owner’s leaning upon the animal is bound up with the formal presentation of the sheep before Hashem.