APA (7th ed.) Citation

Roberts, W. (2008). Printers' Marks A Chapter in the History of Typography. Project Gutenberg.

Chicago Style (17th ed.) Citation

Roberts, W. Printers' Marks A Chapter in the History of Typography. Project Gutenberg, 2008.

MLA (9th ed.) Citation

Roberts, W. Printers' Marks A Chapter in the History of Typography. Project Gutenberg, 2008.

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