What's a good literature on Design Patterns?

Question

Do you have good literature recommendation for Design Patterns, especially for Data Access layers.

I'm searching for patterns like Repository and Unit of Work. I need those for implementing WebServices, MVC web applications and MVVM desktop applications.

Answer 1

If you are searching specifically for Repository and Unit Of Work patterns then i suggest that you don't read full books because they discuss them i a generic way and you will get overwhelmed, instead look for specific implementations for those patterns in the technology area you are working in.
With that being sad, the two authors that stand behind Repostiory and UnitOfWork patterns are Martin Fowler and Eric Evans with their books Patterns of Enterprise Architecture and Domain Driven Design: Tackling Complexity at the Heart of Software respectively, the latter book is followed by a great book called Applying Domain Driven Design and Patterns with Examples in C# and .NET.
Regarding design patterns in general the authoritative reference is The GoF (Gang of Four) book Design Patterns: Elements of Reusable Object Oriented Software System and a very great book that focuses on the most common patterns in an entertaining manner is Head First Design Patterns.

Answer 2

MSDN has some good literature and diagrams on design patterns: http://msdn.microsoft.com/en-us/library/ff649977.aspx

Answer 3

Patterns of Enterprise Architecture

This is the online catalog. The book has the detail and sample code. For me, it's a no-brainer. This is the book you need.