SB 5.20.27

tad-varṣa-puruṣā ṛtavrata-satyavrata-dānavratānuvrata-nāmāno bhagavantaṁ vāyv-ātmakaṁ prāṇāyāma-vidhūta-rajas-tamasaḥ parama-samādhinā yajante.
Synonyms: 
tat-varṣa-puruṣāḥ — the inhabitants of those tracts of land; ṛta-vrata — Ṛtavrata; satya-vrata — Satyavrata; dāna-vrata — Dānavrata; anuvrata — Anuvrata; nāmānaḥ — having the four names; bhagavantam — the Supreme Personality of Godhead; vāyu-ātmakam — represented by the demigod Vāyu; prāṇāyāma — by the practice of regulating the airs within the body; vidhūta — cleansed away; rajaḥ-tamasaḥ — whose passion and ignorance; parama — sublime; samādhinā — by trance; yajante — they worship.
Translation: 
The inhabitants of those islands are also divided into four castes — Ṛtavrata, Satyavrata, Dānavrata and Anuvrata — which exactly resemble brāhmaṇa, kṣatriya, vaiśya and śūdra. They practice prāṇāyāma and mystic yoga, and in trance they worship the Supreme Lord in the form of Vāyu.