Harivamsha 1.35

1.35

ṛco yajūṃṣi sāmāni nirmame yajñasiddhaye
mukhād devān ajanayat pitṝṃś ceśo 'pi vakṣasaḥ |
prajanāc ca manuṣyān vai jaghanān nirmame 'surān |
sādhyāṃs tair ayajan devān ity evam anuśuśrumaḥ //

He fashioned the verses of the Ṛgveda, the Yajurveda formulas, and the chants of the Sāmaveda for the accomplishment of sacrifice; / from his mouth the Lord brought forth the gods, and from his chest the ancestors; / from his organ of generation humans, and from his buttocks he fashioned the asuras. / With those, they sacrificed to the Sādhyas and the gods: thus we have heard.