Dānavavaṃśa-pradhāna-nāmāvalī
Catalogue of Prominent Sons of Danu
क्रान्ता ह्यनायुषः पुत्रा वृत्र स्यापि निबोधत / जज्ञिरे ऽसुमहाघोरा वृत्रस्येन्द्रेण युध्यता
krāntā hyanāyuṣaḥ putrā vṛtra syāpi nibodhata / jajñire 'sumahāghorā vṛtrasyendreṇa yudhyatā
The sons of Anāyuṣa were fierce in prowess; and know also of Vṛtra. As Vṛtra battled Indra, most dreadful asuras were born from him.