Owen, W. V.
Ronald Press, 1958
Buku Teks
Smith, George Albert, author
Richard D. Irwin, 1959
Buku Teks
Appleby, Robert C., author
Pitman, 1981
Buku Teks
Woody, Robert Henley, author
Jossey-Bass, 1989
Buku Teks
Certo, Samuel C.
Allyn and Bacon, 1989
Buku Teks