Vishnupurana 4.1.15

4.1.15

tasyāpy utkalagayavinatasaṃjñās trayaḥ putrā babhūvuḥ ||

Before the evolution of the mundane egg, existed Brahmá, who was Hirańyagarbha, the form of that supreme Brahma which consists of Vishńu as identical with the Rig, Yajur, and Sáma Vedas; the primeval, uncreated cause of all worlds. From the right thumb of Brahmá was born the patriarch Daksha; his daughter was Aditi, who was the mother of the sun. The Manu Vaivaswata was the son of the celestial luminary; and his sons were Ikshwáku, Nriga, Dhrisht́a, Śaryáti, Narishyanta, Pránśu, Nábhága, Nedisht́a, Karúsha, and Prishadhra. Before their birth, the Manu being desirous of sons, offered a sacrifice for that purpose to Mitra and Varuńa; but the rite being deranged, through an irregularity of the ministering priest, a daughter, Ilá, was produced. Through the favour of the two divinities, however, her sex was changed, and she became a man, named Sudyumna. At a subsequent period, in consequence of becoming subject to the effects of a malediction once pronounced by Śiva, Sudyumna was again transformed to a woman in the vicinity of the hermitage of Budha, the son of the deity of the moon. Budha saw and espoused her, and had by her a son named Purúravas. After his birth, the illustrious Rishis, desirous of restoring Sudyumna to his sex, prayed to the mighty Vishńu, who is the essence of the four Vedas, of mind, of every thing, and of nothing; and who is in the form of the sacrificial male; and through his favour Ilá once more became Sudyumna, in which character he had three sons, Utkala, Gaya, and Vinata.