"(Uttering), bhuh,’ Prajapati generated this earth. (Uttering) bhuvah ’ he generated the air, and (Uttering) svah ' he generated the sky. This universe is co-extensive with these worlds. (The fire) is placed with the whole. Saying bhuh,’ Prajapati generated the Brahman ; saying bhuvah,’ he generated the Kshattra ; (and saying) ‘svah,’ he generated the Vis. The fire is placed with the whole. (Saying) bhuh,’ Prajapati generated himself ; (saying) bhuvah,’ he generated offspring; saying ‘svah,’ he generated animals. This world is so much as self, offspring, and animals. (The fire) is placed with the whole."
January 1, 1970
https://en.wikiquote.org/wiki/Shatapatha_Brahmana