Cita APA (7a ed.)

Olsen, R. (2008). Design patterns in Ruby (1st edition.). Addison-Wesley.

Cita Chicago Style (17a ed.)

Olsen, Russ. Design Patterns in Ruby. 1st edition. Upper Saddle River, NJ: Addison-Wesley, 2008.

Cita MLA (9a ed.)

Olsen, Russ. Design Patterns in Ruby. 1st edition. Addison-Wesley, 2008.