共 6 条
[1]
EDWARDS A, 1938, SOCIAL EC GROUPING G, P1
[3]
*US CENS BUR, 1930, POPULATION, V4, P1712
[4]
*US CENS BUR, 1930, POPULATION, V3, P1229
[5]
WEEKS HS, 1938, RES STUDIES STATE CO, V6, P107
[6]
1939, PREDICTING SUCCESS F, P138