APA (7th ed.) Citation

Riley-Smith, J. S. C. (2009). What were the Crusades? (4.ed.). Macmillan.

Chicago Style (17th ed.) Citation

Riley-Smith, Jonathan Simon Christopher. What Were the Crusades? 4.ed. London: Macmillan, 2009.

MLA (8th ed.) Citation

Riley-Smith, Jonathan Simon Christopher. What Were the Crusades? 4.ed. Macmillan, 2009.