Smith, R. J., Butler, B. R., & Le Bold, W. K. (1983). Engineering as a career. New York : McGraw-Hill.

Smith, Ralph J., Blaine R. Butler, and William K. Le Bold. Engineering as a Career. New York : McGraw-Hill, 1983.

Smith, Ralph J., et al. Engineering as a Career. New York : McGraw-Hill, 1983.