APA (7th ed.) Citation

Bunyan, J. (2007). The Pilgrim's Progress. Project Gutenberg.

Chicago Style (17th ed.) Citation

Bunyan, John. The Pilgrim's Progress. Project Gutenberg, 2007.

MLA (9th ed.) Citation

Bunyan, John. The Pilgrim's Progress. Project Gutenberg, 2007.

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