Cite

California : minor civil divisions / Bureau of the Census, 1930.

MLA

of the Census, United States. Bureau. California : Minor Civil Divisions / Bureau of the Census, 1930. U.S. Govt. Print. Off., 1934. https://collections.library.yale.edu/catalog/15821475.

APA, 6th edition

of the Census, U. S. B. (1934). California : minor civil divisions / Bureau of the Census, 1930. [Maps]. U.S. Govt. Print. Off., https://collections.library.yale.edu/catalog/15821475.