10.
The Discourse on the Factors of Enlightenment
375.
"And what, monks, is the path leading to the unconditioned?
The seven factors of enlightenment.
This is called, monks, the path leading to the unconditioned, etc.
The tenth.
Bojjhaṅga Sutta [SN 43.10, PTS 4.361]
Also known as: Bojjhaṅgasuttaṃ