Cita APA (7a ed.)

Pattis, R. E., Roberts, J., & Stehlik, M. (1995). Karel the robot: A gentle introduction to the art of programming (2nd ed.). Wiley.

Cita Chicago Style (17a ed.)

Pattis, Richard E., Jim Roberts, y Mark Stehlik. Karel the Robot: A Gentle Introduction to the Art of Programming. 2nd ed. New York: Wiley, 1995.

Cita MLA (8a ed.)

Pattis, Richard E., et al. Karel the Robot: A Gentle Introduction to the Art of Programming. 2nd ed. Wiley, 1995.