Skandapurana 5.5.5

5.5.5

babhūva sa svayaṃ dhīmānadhvaryuryajñakarmaṇi.
tasminhotā ca śāṃḍilyo brahmā gautama eva ca..6.5.5..

The wise sage himself became the adhvaryu priest in the sacrificial rite;
in it, Śāṇḍilya was the hotṛ, and Gautama was the brahmā.