Śrīmad-Bhāgavatam · Text 1.3.11
Who is speaking and story frame
षष्ठमत्रेरपत्यत्वं वृत: प्राप्तोऽनसूयया ।
आन्वीक्षिकीमलर्काय प्रह्लादादिभ्य ऊचिवान् ॥ ११ ॥
ṣaṣṭham atrer apatyatvaṁ
vṛtaḥ prāpto ’nasūyayā
ānvīkṣikīm alarkāya
prahlādādibhya ūcivān
The sixth incarnation of the puruṣa was the son of the sage Atri. He was born from the womb of Anasūyā, who prayed for an incarnation. He spoke on the subject of transcendence to Alarka, Prahlāda and others [Yadu, Haihaya, etc.].
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