Lewis, William Arthur, 1915-
Public Affairs, 1951
Buku Teks
Tinbergen, Jan, 1903-
North-Holland Publishing , 1952
Buku Teks
Lewis, William Arthur, 1915-
Harper & Row, 1966
Buku Teks
Keilhau, Wilhelm
George Allen & Unwin, 1951
Buku Teks
Glassburner, Bruce
ASEAN-Australia Joint Research Project, 1984
Buku Teks