Friend, Irwin
John Wiley & Sons, 1954
Buku Teks
Thurow, Lester C., author
HarperCollins, 1999
Buku Teks
Hansen, Alvin Harvey, 1887-1975, author
W.W. Norton, 1951
Buku Teks
Goldsmith, Raymond W.
Prenceton University Press, 1955
Buku Teks
Blume, Marshall E.
John Wiley & Sons, 1978
Buku Teks