United States. Census Office. 6th Census, 1840, & United States. National Archives and Records Service. (1973). Schedule of mines, agriculture, commerce, manufactures, etc. of 1840 census for Illinois. National Archives.
Chicago Style (17th ed.) CitationUnited States. Census Office. 6th Census, 1840, and United States. National Archives and Records Service. Schedule of Mines, Agriculture, Commerce, Manufactures, Etc. of 1840 Census for Illinois. Washington, D.C.: National Archives, 1973.
MLA (8th ed.) CitationUnited States. Census Office. 6th Census, 1840, and United States. National Archives and Records Service. Schedule of Mines, Agriculture, Commerce, Manufactures, Etc. of 1840 Census for Illinois. National Archives, 1973.
Warning: These citations may not always be 100% accurate.