United States. Census Office. 6th Census, 1840, & United States. National Archives and Records Service. (1974). 1840 Census schedules of mines, agriculture, commerce, and manufacturing for Massachusetts. National Archives.
Chicago Style (17th ed.) CitationUnited States. Census Office. 6th Census, 1840, and United States. National Archives and Records Service. 1840 Census Schedules of Mines, Agriculture, Commerce, and Manufacturing for Massachusetts. Washington, D.C.: National Archives, 1974.
MLA引文United States. Census Office. 6th Census, 1840, and United States. National Archives and Records Service. 1840 Census Schedules of Mines, Agriculture, Commerce, and Manufacturing for Massachusetts. National Archives, 1974.
警告：這些引文格式不一定是100％准確.