APA (7th ed.) Citation

Greely, A. W. (2011). Explorers and Travellers. Project Gutenberg.

Chicago Style (17th ed.) Citation

Greely, Adolphus W. Explorers and Travellers. Project Gutenberg, 2011.

MLA (9th ed.) Citation

Greely, Adolphus W. Explorers and Travellers. Project Gutenberg, 2011.

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