APA (7th ed.) Citation

Sullivan, W. G., Wicks, E. M., & Koelling, C. P. Engineering economy (15th ed.).

Chicago Style (17th ed.) Citation

Sullivan, William G., Elin M. Wicks, and C. Patrick Koelling. Engineering Economy. 15th ed.

MLA (8th ed.) Citation

Sullivan, William G., et al. Engineering Economy. 15th ed.