Pra quem deseja estudar Orientação a Objetos.

Pra quem deseja estudar Orientação a Objetos, recomendo python pois a linha de aprendizado é mais curta que em java e outras linguagens, segue uns links abaixo, recomendo o livro Python Programming for the Absolute Beginner, 3rd Edition by Michael Dawson pra quem esta começando:

• Python Types and Objects
  by Shalabh Chaturvedi
• Python Attributes and Methods
  by Shalabh Chaturvedi
• Python official documentation
• PEP 252 -- Making Types Look More Like Classes
  and many other PEPs like PEP 3115 -- Metaclasses in Python 3000
  and PEP 3119 -- Introducing Abstract Base Classes
  by Guido van Rossum and others
• Python’s super() considered super!
  and PEP 3135 -- New Super
  by Raymond Hettinger
• A Guide to Python's Magic Methods
  by Rafe Kettler
• Improve Your Python: Python Classes and Object Oriented Programming
  by Jeff Knupp
• Drastically Improve Your Python: Understanding Python's Execution Model
  by Jeff Knupp
• OOP Concepts in Python 2.x - Part 1
  by Leonardo Giordani
• OOP Concepts in Python 2.x - Part 2
  by Leonardo Giordani
• OOP Concepts in Python 2.x - Part 3
  by Leonardo Giordani