Gaya APA

H., K, K., L., J, R. (1991). Purchasing Managers Guide To Model Letters. Memos. And Forms . New Jersey: Prentice-Hall.

Gaya MLA

H., Killen, Kenneth., L., Janson, Robert. "Purchasing Managers Guide To Model Letters. Memos. And Forms". New Jersey: Prentice-Hall, 1991. Text.