9.
The Discourse on Impermanence
257.
"There are these three feelings, monks, impermanent, conditioned, dependently arisen, subject to destruction, subject to falling, subject to fading away, having the nature of cessation.
Which three?
Pleasant feeling, unpleasant feeling, neither-unpleasant-nor-pleasant feeling -
these, monks, are the three feelings, impermanent, conditioned, dependently arisen, subject to destruction, subject to falling, subject to fading away, having the nature of cessation."
The ninth.