compiled by Jonathan French Scott and Alexander Baltzly
F.S. Crofts & Co., 1930
Buku Teks
Stearns, Peter N.
Macmillan, 1967
Buku Teks
Smith, Bonnie G.
D.C. Heath, 1989
Buku Teks
Burns, Arthur F.
National Bureau of Economics Reseach, 1934
Buku Teks
Stromberg, Roland N.
Prentice-Hall, 1990
Buku Teks