APA (7th ed.) Citation

Parker, H. M. D., & Watson, G. (1961). The Roman legions. Heffer & Sons.

Chicago Style (17th ed.) Citation

Parker, Henry Michael Denne, and G.R Watson. The Roman Legions. Cambridge [England]: Heffer & Sons, 1961.

MLA (9th ed.) Citation

Parker, Henry Michael Denne, and G.R Watson. The Roman Legions. Heffer & Sons, 1961.

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