Design Patterns Books

• Design Patterns: Elements of Reusable Object-Oriented Software - [buy] - GoF
• Design Patterns Explained - [buy] - Shalloway and Trott
• Design Patterns in Java - [buy] - Metsker and Wake
• Head First Design Patterns - [buy] - Freeman and Robson
• Refactoring to Patterns - [buy] - Joshua Kerievsky