How To Defend A Bridge Hand By William S. Root Pdf Link -

Many defenders win a trick with their Ace that they could have won later. Root shows that by ducking once, you can cut declarer’s communications.

"The searchable PDF is a lifesaver. I keep it open on my iPad during online games (with permission, of course). When I face a defensive problem, I quickly search Root's advice. It's like having a coach beside you." — David L., London How to Defend a Bridge Hand by William S. Root PDF