What can someone tell me about Ngo Cho Kun and Northern Tai Chor and Southern Tai Chor ? Is southern Tai Chor the art that lead to the creation of alot of Southern arts that use Sam Chian , Som Bo Jin , Nine Step Push or 3 step Push , Sup Luk Dung , Sui Lien Tao ? what are some good books on Northern Tai Chor and Southern Tai Chor ?