How to Bid in Bridge: 8 Steps (with Pictures) - wikiHow
PRECISION BIDDING SYSTEM IN BRIDGE, By C. C. Wei 9780486211718 | eBay
Advanced Bridge Bidding for the 21st Century: An Up-To-Date Presentation of the Two-Over-One Game Forcing Bidding System Used by the Top Players in the World, Including Upgrades and Refinements. by Max Hardy
Australian Bridge Federation » Bidding/Play/Defence Tips