Tolles, N. Arnold
Prentice-Hall, 1964
Buku Teks
White, James L., author
Washington Square Press, 1966
Buku Teks
Smith, Thomas C., author
Standford University Press, 1959
Buku Teks
Smith, Thomas C., author
Standford University Press, 1965
Buku Teks
Watson, H.B., author
Oxford University Press , 1949
Buku Teks