File:The first Balisong knife made by Ernest Emerson.jpg - Wikipedia
Weapons Lies of P Wiki
Butterfly sword - Wikipedia
Knife - Official TF2 Wiki Official Team Fortress Wiki
Bolo knife - Wikipedia
balisong-butterfly knife, fortel knife
Will Hirsch
Knife - Wikipedia
Butterflying - Wikipedia
Benchmade - Wikipedia
The Knife and the Butterfly - Wikipedia
Balisong Flippers: Who are they? - Knives Illustrated