Padmapurana 1.46.157

Padmapurāṇa 1.46.157

prāṇāyāmayutāṃtasmādgāyatrīṃjapanārada
nāradauvācaprāṇāyāmāḥkathaṃbrahmanpratyekākṣaradevatāḥ