Kalay, Y. E. (1987). Graphic introduction to programming. Wiley.
Cita Chicago (17th ed.)Kalay, Yehuda E. Graphic Introduction to Programming. New York: Wiley, 1987.
Cita MLA (9th ed.)Kalay, Yehuda E. Graphic Introduction to Programming. Wiley, 1987.
Atenció: Aquestes cites poden no estar 100% correctes.