Toffler, Alvin, author
Pantja Simpati, 1989
Buku Teks
Derbolav, Josef, author
I.B. Tauris, 2008
Buku Teks
Heldman, Robert K., author
D. C. McGraw-Hill , 1993
Buku Teks
Cambridge University Press, 1965
Buku Teks
Locke, John, author
J.M. Dent and Sons , 1947
Buku Teks