One verse

Srimad Bhagavatam 11.14.35

11.14.35

एवं प्रणवसंयुक्तं प्राणमेव समभ्यसेत् । दशकृत्वस्‍त्रिषवणं मासादर्वाग् जितानिल: ॥ ३५ ॥

evaṁ praṇava-saṁyuktaṁ prāṇam eva samabhyaset daśa-kṛtvas tri-ṣavaṇaṁ māsād arvāg jitānilaḥ

evam
thus
praṇava
with the syllable om
saṁyuktam
joined
prāṇam
the prāṇāyāma system of controlling the bodily airs
eva
indeed
samabhyaset
one should carefully practice
daśa-kṛtvaḥ
ten times
tri-savanam
at sunrise, noon and sunset
māsāt
one month
arvāk
after
jita
one will conquer
anilaḥ
the life air

Being fixed in the oṁkāra, one should carefully practice the prāṇāyāma system ten times at each sunrise, noon and sunset. Thus, after one month one will have conquered the life air.