APA (7th ed.) Citation

Cowan, R., Hook, A., & Windrow, M. (2007). Roman battle tactics, 109 BC-AD 313. Osprey.

Chicago Style (17th ed.) Citation

Cowan, Ross, Adam Hook, and Martin Windrow. Roman Battle Tactics, 109 BC-AD 313. Oxford: Osprey, 2007.

MLA (9th ed.) Citation

Cowan, Ross, et al. Roman Battle Tactics, 109 BC-AD 313. Osprey, 2007.