CC Ādi 6.22

sei nārāyaṇera mukhya aṅga, — advaita
‘aṅga’-śabde aṁśa kari’ kahe bhāgavata
Word for word: 
sei — that; nārāyaṇera — of Lord Nārāyaṇa; mukhya aṅga — the primary part; advaita — Advaita Ācārya; aṅga-śabde — by the word aṅga; aṁśa kari’ — taking as a plenary portion; kahe — says; bhāgavata — Śrīmad-Bhāgavatam.
Translation: 
Śrī Advaita is the principal limb [aṅga] of Nārāyaṇa. Śrīmad-Bhāgavatam speaks of “limb” [aṅga] as “a plenary portion” [aṁśa] of the Lord.