APA (7th ed.) Citation

Whittaker, N. (1921). German Jesuits in the seventeenth century.

Chicago Style (17th ed.) Citation

Whittaker, Nicholas. German Jesuits in the Seventeenth Century. 1921.

MLA (9th ed.) Citation

Whittaker, Nicholas. German Jesuits in the Seventeenth Century. 1921.

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