APA (7th ed.) Citation

Norton, W. H. (2012). The Elements of Geology. Project Gutenberg.

Chicago Style (17th ed.) Citation

Norton, William Harmon. The Elements of Geology. Project Gutenberg, 2012.

MLA (9th ed.) Citation

Norton, William Harmon. The Elements of Geology. Project Gutenberg, 2012.

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