Cita APA (7th ed.)

Heinritz, S. F., & Farrell, P. V. (1981). Purchasing: Principles and applications (6th ed.). Prentice-Hall.

Cita Chicago (17th ed.)

Heinritz, Stuart F., i Paul V. Farrell. Purchasing: Principles and Applications. 6th ed. Englewood Cliffs, N.J: Prentice-Hall, 1981.

Cita MLA (9th ed.)

Heinritz, Stuart F., i Paul V. Farrell. Purchasing: Principles and Applications. 6th ed. Prentice-Hall, 1981.