Kavyadarsha 2.204

2.204

nisargādipadair atra hetuḥ sākṣān nivartitaḥ &
uktaṃ ca surabhitvādi phalaṃ tat sā vibhāvanā //iti vibhāvanācakram//

Here, by words such as 'by nature,' the cause is directly eliminated,
and the effect, such as fragrance, is stated: therefore that is unusual causation.
Thus ends the cycle of unusual causation (vibhāvanā).