Parashas Acharei Mos · Passuk 16:32
Chabad.org — English translation + Rashi
Torah Temima points to Yerushalmi Horayos 3:2.
English: From where do we include another who was appointed (not only the anointed)? From “and the Kohen shall atone.”
Inclusion of appointed Kohen Gadol
A Kohen Gadol appointed by investiture (without anointing oil) is also empowered to perform the Yom Kippur service.