Dyfyniad APA

Bernard, D. (1977). Charging For Computer Services: Principles and Guidelines. Petrocell.

Dyfyniad Arddull Chicago

Bernard, Dan. Charging For Computer Services: Principles and Guidelines. New York: Petrocell, 1977.

Dyfyniad MLA

Bernard, Dan. Charging For Computer Services: Principles and Guidelines. Petrocell, 1977.

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