CC Antya 20.121

trayodaśe — jagadānanda mathurā yāi’ āilā
mahāprabhu deva-dāsīra gīta śunilā
Word for word: 
trayodaśe — in the thirteenth chapter; jagadānanda — Jagadānanda Paṇḍita; mathurā yāi’ — going to Mathurā; āilā — returned; mahāprabhu — Śrī Caitanya Mahāprabhu; deva-dāsīra — of the deva-dāsī dancing girl; gīta śunilā — heard the song.
Translation: 
The thirteenth chapter tells how Jagadānanda Paṇḍita went to Mathurā and returned and how Śrī Caitanya Mahāprabhu by chance heard a song sung by a deva-dāsī dancing girl.