Srimad Bhagavatam Canto 10, Chapter 18, Text 30

SB 10.18.30

drstva pralambam nihatam
 balena bala-salina
gopah su-vismita asan
 sadhu sadhv iti vadinah
 
Translation: 
 
The cowherd boys were most astonished to see how the powerful Balarama had killed the demon Pralamba, and they exclaimed, “Excellent! Excellent!”
Srimad Bhagavatam Canto 10, Chapter 18, Text 29
Srimad Bhagavatam Canto 10, Chapter 18, Text 31