APA (7th ed.) Citation

(1990). The 1990 United States census. Project Gutenberg.

Chicago Style (17th ed.) Citation

The 1990 United States Census. Champaign, Ill: Project Gutenberg, 1990.

MLA (9th ed.) Citation

The 1990 United States Census. Project Gutenberg, 1990.

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