Srimad Bhagavatam Canto 12, Chapter 13, Text 17

SB 12.13.17

ksetranam caiva sarvesam
 yatha kasi hy anuttama
tatha purana-vratanam
 srimad-bhagavatam dvijah
 
Translation: 
 
O brahmanas, in the same way that the city of Kasi is unexcelled among holy places, Srimad-Bhagavatam is supreme among all the Puranas.
Srimad Bhagavatam Canto 12, Chapter 13, Text 16
Srimad Bhagavatam Canto 12, Chapter 13, Text 18