Cita APA (7a ed.)

Bergin, J., Stehlik, M., Roberts, J., & Pattis, R. (1997). Karel ++: A gentle introduction to the art of object-oriented programming (1a ed.). John Wiley and Sons.

Cita Chicago Style (17a ed.)

Bergin, Joseph, Mark Stehlik, Jim Roberts, y Richard Pattis. Karel ++: A Gentle Introduction to the Art of Object-oriented Programming. 1a ed. Nueva York: John Wiley and Sons, 1997.

Cita MLA (9a ed.)

Bergin, Joseph, et al. Karel ++: A Gentle Introduction to the Art of Object-oriented Programming. 1a ed. John Wiley and Sons, 1997.