Clark, Victor S.
History of manufactures in the United States volume III 1893-1928
Peter Smith, 1949
 Buku Teks
Fogel, Robert William
Railroads and American economic growth : essays in econometrics history
Johns Hopkins Press, 1964
 Buku Teks
Encyclopedia of American history : erlarged and update
edited by Richard B. Morris
Harper and Row , 1965
 Buku Referensi
The American family in social-historical/ Michael Gordon,(ed)
St.Martin's Press, 1983
 Buku Teks
Robertson, Ross M.
History of the American economy
Harcourt, Brace & World, 1964
 Buku Teks