HD - Industries, Land Use, Labor 734,981
HC - Economic History and Conditions 378,869
HV - Social Pathology, Criminology 306,097
HQ - Family, Marriage, Women 261,992
HF - Commerce 243,474
HB - Economic Theory and Demography 223,971
HG - Finance 201,620
HN - Social History and Conditions 123,688
HE - Transportation and Communications 111,206
HT - Communities, Classes, Races 108,433
HM - Sociology 106,494
HX - Socialism, Communism, Anarchism 83,302
HJ - Public Finance 79,980
HA - Statistics 57,049
H - Social Science 42,076
HS - Societies 15,390
F - General American History 3
B - Philosophy 2
E - United States History 2
N - Visual Arts 2
NC - Drawing, Design, Illustration 1
PS - American Literature 1