APA (7th ed.) Citation

Wiegler, P. (1930). The infidel emperor and his struggles against the pope: A chronicle of the thirteenth century. G. Routledge.

Chicago Style (17th ed.) Citation

Wiegler, Paul. The Infidel Emperor and His Struggles Against the Pope: A Chronicle of the Thirteenth Century. London: G. Routledge, 1930.

MLA (9th ed.) Citation

Wiegler, Paul. The Infidel Emperor and His Struggles Against the Pope: A Chronicle of the Thirteenth Century. G. Routledge, 1930.