Shiva Purana
तस्याधारः स्थितो नागस्स च विष्णुः प्रकीर्तितः ॥ ब्रह्मणो वचसो हेतोर्बिभर्ति सकलं त्विदम् ॥ ११ ॥
Its support is the serpent Śeṣa. He is glorified as Viṣṇu. At the instance of Brahmā he supports all this.
english translation
tasyAdhAraH sthito nAgassa ca viSNuH prakIrtitaH ॥ brahmaNo vacaso hetorbibharti sakalaM tvidam ॥ 11 ॥
hk transliteration by Sanscript