APA (7th ed.) Citation

Costa, B. F. d. (2012). The Pre-Columbian Discovery of America by the Northmen. Project Gutenberg.

Chicago Style (17th ed.) Citation

Costa, B. F. de. The Pre-Columbian Discovery of America by the Northmen. Project Gutenberg, 2012.

MLA (9th ed.) Citation

Costa, B. F. de. The Pre-Columbian Discovery of America by the Northmen. Project Gutenberg, 2012.

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