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.
Dyfyniad Arddull ChicagoUnited 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.
Dyfyniad MLAUnited 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.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.