Pattis, R. E. (1981). Karel the robot: A gentle introdcution to the art of programming. John Wiley and Sons.
Παραπομπή Chicago StylePattis, Richard E. Karel the Robot: A Gentle Introdcution to the Art of Programming. New York: John Wiley and Sons, 1981.
Παραπομπή MLAPattis, Richard E. Karel the Robot: A Gentle Introdcution to the Art of Programming. John Wiley and Sons, 1981.
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