APA (7th ed.) Citation

Guignebert, C. (1961). Ancient, medieval, and modern Christianity. University Books.

Chicago Style (17th ed.) Citation

Guignebert, Charles. Ancient, Medieval, and Modern Christianity. New Hyde Park, N.Y.: University Books, 1961.

MLA (9th ed.) Citation

Guignebert, Charles. Ancient, Medieval, and Modern Christianity. University Books, 1961.