Bhagavatapurana 11.14.32

11.14.32

/0 śrī-bhagavān uvāca
sama āsana āsīnaḥ sama-kāyo yathā-sukham /
hastāv utsaṅga ādhāya sva-nāsāgra-kṛtekṣaṇaḥ //

32. & 33. The Lord said:—Seated on a level ground, with his body erect, in a comfortable posture, placing the two hands on his lap, and fixing the eyes on the tip of his nose, he should cleanse the passages of the vital breath (Prana) by means of the processes known as Puraka, Rechaka and Kumbhaka or in the reverse order, and should gradually and slowly practise this course keeping the senses under control.