APA (7th ed.) Citation

United States. Patent Office. (2007). The Classification of Patents. Project Gutenberg.

Chicago Style (17th ed.) Citation

United States. Patent Office. The Classification of Patents. Project Gutenberg, 2007.

MLA (9th ed.) Citation

United States. Patent Office. The Classification of Patents. Project Gutenberg, 2007.

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