CC Ādi 2.63

vadanti tat tattva-vidas
tattvaṁ yaj jñānam advayam
brahmeti paramātmeti
bhagavān iti śabdyate
Synonyms: 
vadanti — they say; tat — that; tattva-vidaḥ — learned souls; tattvam — the Absolute Truth; yat — which; jñānam — knowledge; advayam — nondual; brahma — Brahman; iti — thus; paramātmā — Paramātmā; iti — thus; bhagavān — Bhagavān; iti — thus; śabdyate — is known.
Translation: 
“Learned transcendentalists who know the Absolute Truth say that it is nondual knowledge and is called impersonal Brahman, the localized Paramātmā and the Personality of Godhead.”
Purport: 

This text is from Śrīmad-Bhāgavatam (1.2.11).