APA (7th ed.) Citation

Viljoen, S. (1974). Economic systems in world history / (by) Stephan Viljoen. Longman.

Chicago Style (17th ed.) Citation

Viljoen, Stephan. Economic Systems in World History / (by) Stephan Viljoen. London: Longman, 1974.

MLA (9th ed.) Citation

Viljoen, Stephan. Economic Systems in World History / (by) Stephan Viljoen. Longman, 1974.

Warning: These citations may not always be 100% accurate.