APA (7th ed.) Citation

United States. Census Office & Duke University. Library. (1870). [Census schedules of the 9th and 10th censuses of the United States, 1870, 1880]: Colorado. U.S. Census Office?].

Chicago Style (17th ed.) Citation

United States. Census Office and Duke University. Library. [Census Schedules of the 9th and 10th Censuses of the United States, 1870, 1880]: Colorado. [Washington, D.C.: U.S. Census Office?], 1870.

MLA (8th ed.) Citation

United States. Census Office and Duke University. Library. [Census Schedules of the 9th and 10th Censuses of the United States, 1870, 1880]: Colorado. U.S. Census Office?], 1870.