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Object-Oriented (OOD/OOP) 
Design Patterns Dictionary (in C++ and Java) [in C#] Object-Oriented System Development
Adaptive Object-Oriented Software: Patterns for Adaptive Programming (AP)
Introduction To Design Patterns with Java (Bob Tarr)  
Object Oriented Programming Unified Modeling Language (UML) Books
Interface Design: Best Practices in Object-Oriented API Design in Java
Objects and Java: Building Object-Oriented, Multi-Threaded Applications with Java
Patterns of Enterprise Application Architecture (Martin Fowler)
Bringing Design to Software Naked Objects
Recommanded Approach to Software Development (PDF) Working with Objects (PDF, 497p) [Previous, 466p]
Object-Oriented Software Composition (by O. Nierstrasz and D. Tsichritzis)
NeXTStep Programming: Step One, Object-Oriented Applications (671 pages, PDF)
Ada 95: The Craft of Object-Oriented Programming Object-Oriented Programming with ANSI C
OBJECT-ORIENTED PROGRAMMING and THE OBJECTIVE-C LANGUAGE
Object Oriented Perl (PDF) [Mirror] Java Design Pattern: A Tutorial
Integration Patterns Principles of Object-Oriented Programming in Java
Data Access Patterns: Database Interactions in Object-Oriented Applications
An Introduction to C++ and Object Oriented Programming, by Ian D Chivers, January 1999
Introduction to Object-Oriented Programming Using C++ (Peter Müller) [Mirror] [Mirror] [Printing Version]
Data Structures and Algorithms with Object-Oriented Design Patterns in Java (B.R. Preiss)
Data Structures and Algorithms with Object-Oriented Design Patterns in C++ (B.R. Preiss)
Data Structures and Algorithms with Object-Oriented Design Patterns in C# (B.R. Preiss)