APA (7th ed.) Citation

Horne, C. F., Rudd, J., Austin, W. F., & Johnson, R. (2004). The Great Events by Famous Historians, Volume 06 (From Barbarossa to Dante). Project Gutenberg.

Chicago Style (17th ed.) Citation

Horne, Charles F., John Rudd, Walter F. Austin, and Rossiter Johnson. The Great Events by Famous Historians, Volume 06 (From Barbarossa to Dante). Project Gutenberg, 2004.

MLA (9th ed.) Citation

Horne, Charles F., et al. The Great Events by Famous Historians, Volume 06 (From Barbarossa to Dante). Project Gutenberg, 2004.

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