APA (7th ed.) Citation

Cowan, R., & Ó'Brógáin, S. (2015). Roman legionary, AD 284-337: The age of Diocletian and Constantine (1st published.). Osprey.

Chicago Style (17th ed.) Citation

Cowan, Ross, and Seán Ó'Brógáin. Roman Legionary, AD 284-337: The Age of Diocletian and Constantine. 1st published. Oxford: Osprey, 2015.

MLA (9th ed.) Citation

Cowan, Ross, and Seán Ó'Brógáin. Roman Legionary, AD 284-337: The Age of Diocletian and Constantine. 1st published. Osprey, 2015.