APA (7th ed.) Citation

Putnam, G. R. (2013). Nautical Charts. Project Gutenberg.

Chicago Style (17th ed.) Citation

Putnam, G. R. Nautical Charts. Project Gutenberg, 2013.

MLA (9th ed.) Citation

Putnam, G. R. Nautical Charts. Project Gutenberg, 2013.

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