Australian Government Publishing Service , 1979
Buku Teks
Lewis, William Arthur, author
University of Ghana by the Ghana Pub, 1971
Buku Teks
Lockwood, William W., author
Princeton Princeton University Press , 1954
Buku Teks
Broadbridge, Seymour
Frank Cass, 1976
Buku Teks
Arndt, H. W. (Heinz Wolfgang), 1915-2002, author
F.W. Cheshire , 1968
Buku Teks