Bhagavatapurana 3.8.15

3.8.15

tal loka-padmaṃ sa u eva viṣṇuḥ prāvīviśat sarva-guṇāvabhāsam /
tasmin svayaṃ vedamayo vidhātā svayambhuvaṃ yaṃ sma vadanti so 'bhūt //

15. O wise one! the glorious Vishnu Himself entered that world-lotus which brings to light all the objects necessary for the jiva's experience; and within it, was born, that Maker of the world, himself, the embodiment of the Vedas whom the wise call Svayambhu.