Cita APA (7th ed.)

Perrett, H., & Lethem, F. J. (1980). Human factors in project work. World Bank.

Cita Chicago (17th ed.)

Perrett, Heli, i Francis J. Lethem. Human Factors in Project Work. Washington, D.C: World Bank, 1980.

Cita MLA (9th ed.)

Perrett, Heli, i Francis J. Lethem. Human Factors in Project Work. World Bank, 1980.