Tactics
1. The manual of chess combinations
2. The encyclopedia of chess combinations
3. Improve Your Chess Tactics: 700 Practical Lessons & Exercises
Openings
1. Dismantling the Sicilian
2. Grandmaster Repertoire 7: The Caro-Kann
Endgame
1. 100 Endgames you must know
2. Any of the books or DVDs by Karsten Mueller - they are all excellent
