Cita APA (7a ed.)

Heinritz, S. (1986). Purchasing principle and applications (7th edition.). Prentice Hall.

Cita Chicago Style (17a ed.)

Heinritz, Stuart. Purchasing Principle and Applications. 7th edition. United states of America: Prentice Hall, 1986.

Cita MLA (9a ed.)

Heinritz, Stuart. Purchasing Principle and Applications. 7th edition. Prentice Hall, 1986.