Cita APA (7th ed.)

(1988). Four software tools: With WordPerfect, VP-planner, and dBase III plus / Tim Duffy.

Cita Chicago (17th ed.)

Four Software Tools: With WordPerfect, VP-planner, and DBase III Plus / Tim Duffy. 1988.

Cita MLA (9th ed.)

Four Software Tools: With WordPerfect, VP-planner, and DBase III Plus / Tim Duffy. 1988.

Atenció: Aquestes cites poden no estar 100% correctes.