APA (7th ed.) Citation

Horne, J. (2010). A Companion to World War I. Wiley-Blackwell.

Chicago Style (17th ed.) Citation

Horne, John. A Companion to World War I. Chichester, West Sussex [u.a.]: Wiley-Blackwell, 2010.

MLA (8th ed.) Citation

Horne, John. A Companion to World War I. Wiley-Blackwell, 2010.