http://eduardopires.net.br/2013/05/single-responsibility-principle-srp/

http://eduardopires.net.br/2013/05/open-closed-principle-ocp/

http://brizeno.wordpress.com/tag/liskov-substitution-principle/

http://dyegocomy.com/blog/interface-segregation-principle/

http://dyegocomy.com/blog/dependency-inversion-principle/

http://butunclebob.com/ArticleS.UncleBob.PrinciplesOfOod

http://developingux.com/2010/02/09/solid-development/

http://www.oodesign.com