James, Simon, author
Prentice-Hall, 2000
Buku Teks
Seth, M.L., author
S. Chand, 1969
Buku Teks
Krugman, Paul R., author
Addison-Wesley , 1997
Buku Teks
Watson, Donald Stevenson, author
Houghton Miffiln, 1960
Buku Teks
Boulding, Kenneth E. (Kenneth Ewart), 1910-1993, author
Prentice-Hall, 1958
Buku Teks