APA (7th ed.) Citation

Pattis, R. E. (1981). Karel the robot: A gentle introduction to the art of programming. Wiley.

Chicago Style (17th ed.) Citation

Pattis, Richard E. Karel the Robot: A Gentle Introduction to the Art of Programming. New York: Wiley, 1981.

MLA (8th ed.) Citation

Pattis, Richard E. Karel the Robot: A Gentle Introduction to the Art of Programming. Wiley, 1981.