Garudapurana 1.35.1

1.35.1

śrīgaruḍamahāpurāṇam- 35
hariruvāca /
nyāsādikaṃ pravakṣyāmi gāyattryāḥ śṛṇu śaṅkara /
viśvāmitraṛṣiścaiva savitā cātha devatā //

The glorious Garuḍa Mahāpurāṇa — 35
Hari said:
I shall explain the nyāsa and other rites of the Gāyatrī; listen, O Śaṅkara. / Its ṛṣi is Viśvāmitra, and Savitṛ is its deity;