edited by Reavis Cox and Wroe Alderson
Richard D. Irwin, 1950
Buku Teks
Douglas, Edna
Harper & Row , 1975
Buku Teks
Holloway, Robert J., author
John Wiley & Sons, 1968
Buku Teks
Howard, John A., author
Richard D. Irwin, 1957
Buku Teks
Keegan, Warren J., author
Prentice Hall of India, 1982
Buku Teks