Shiva Purana
एको विष्णुर्नृसिंहात्मा सदर्पश्च महाबलः ॥ जगत्संहारकरणे प्रवृत्तो नरकेसरी ॥ ३२ ॥
It was Viṣṇu alone in the form of the Man-lion, haughty and strong, engaged in the activity of annihilating the universe.
english translation
eko viSNurnRsiMhAtmA sadarpazca mahAbalaH ॥ jagatsaMhArakaraNe pravRtto narakesarI ॥ 32 ॥
hk transliteration by Sanscript