APA (7th ed.) Citation

Ségur, P., Grote, G., & Montgomery, D. H. (2008). The Two Great Retreats of History. Project Gutenberg.

Chicago Style (17th ed.) Citation

Ségur, Philippe-Paul, George Grote, and D. H. Montgomery. The Two Great Retreats of History. Project Gutenberg, 2008.

MLA (9th ed.) Citation

Ségur, Philippe-Paul, et al. The Two Great Retreats of History. Project Gutenberg, 2008.

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