Vayupurana 1.12.24

Vāyupurāṇa 1.12.24

paśyate maṇḍalaṃ sūkṣmaṃ ghoṣaścāsya pravarttate .
ātmānaṃ manyate nityaṃ vāyuḥ sūkṣmaḥ pravarttate .. 12.23 ..