Srimad Bhagavatam Canto 10, Chapter 43, Text 16

SB 10.43.16

vrtau gopaih katipayair
 baladeva-janardanau
rangam vivisatu rajan
 gaja-danta-varayudhau
 
Translation: 
 
My dear King, Lord Baladeva and Lord Janardana, each carrying one of the elephant’s tusks as His chosen weapon, entered the arena with several cowherd boys.
Srimad Bhagavatam Canto 10, Chapter 43, Text 15
Srimad Bhagavatam Canto 10, Chapter 43, Text 17