Sixteenth census of the United States: 1940.
APA Citation
United States. Bureau of the Census., Guernsey, J. (1940). Sixteenth census of the United States: 1940. Washington: U. S. Govt. print. off..
MLA Citation
United States. Bureau of the Census, and John Guernsey. Sixteenth Census of the United States: 1940. Washington: U. S. Govt. print. off., 1940.
Warning: These citations may not always be complete (especially for serials).