APA (7th ed.) Citation

Ledgard, H., Singer, A., & Whiteside, J. (1981). Directions in human factors for interactive systems (3. print.). Springer.

Chicago Style (17th ed.) Citation

Ledgard, Henry, Andrew Singer, and John Whiteside. Directions in Human Factors for Interactive Systems. 3. print. Berlin ; Heidelberg <<[u.a.]>>: Springer, 1981.

MLA (9th ed.) Citation

Ledgard, Henry, et al. Directions in Human Factors for Interactive Systems. 3. print. Springer, 1981.