APA (7th ed.) Citation

Levick, G. M. (2011). Antarctic Penguins A Study of Their Social Habits. Project Gutenberg.

Chicago Style (17th ed.) Citation

Levick, George Murray. Antarctic Penguins A Study of Their Social Habits. Project Gutenberg, 2011.

MLA (9th ed.) Citation

Levick, George Murray. Antarctic Penguins A Study of Their Social Habits. Project Gutenberg, 2011.

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