| 1. | Census micro data ( 1850 , 1860 , 1870 , 1880 , 1900 - 1920 , 1940 - 2000 ) are available from minnesotta population center , university of minessota . the entire 1880 us and 1881 canadian censuses are also available from north atlantic population project
原始个别普查资料（ 1850 , 1860 , 1870 , 1880 , 1900 - 1920 , 1940 - 2000 ）可于明尼苏达大学的明尼苏达人口中心查得。由“北大西洋人口计划”亦可查到1880年全年的美国普查与1881年的加拿大普查资料。 |
