Ramayana
अनन्तरं महाविप्रो गौतमः प्रत्यपूरयत् । वसिष्ठो ऽपि महातेजा इन्द्रयज्ञमथाकरोत् ॥ 7-55-11 ॥
Thereupon the great Brahmin Gautama filled the office of priest in his stead, while Vasishtha of mighty splendor went and performed Indra's sacrifice.
english translation