APA (7th ed.) Citation

WILLEMS, N., EASLY, J. T., & ROLFE, S. T. (1981). Strength of materials. McGraw-hill.

Chicago Style (17th ed.) Citation

WILLEMS, Nicholas, John T. EASLY, and Stanley T. ROLFE. Strength of Materials. New York: McGraw-hill, 1981.

MLA (9th ed.) Citation

WILLEMS, Nicholas, et al. Strength of Materials. McGraw-hill, 1981.