GURPS Compendium 2 p 62
first introduced in 1992 http://www.sjgames.com/gurps/Roleplayer/Roleplayer27/Concentrated-Defense.html
GURPS Wiki
GURPS Wiki
"The material presented here is a community original creation, intended for use with the GURPS system from Steve Jackson Games. This material is not official and is not endorsed by Steve Jackson Games."
READ MORE
GURPS Compendium 2 p 62
first introduced in 1992 http://www.sjgames.com/gurps/Roleplayer/Roleplayer27/Concentrated-Defense.html