Simpson, W.O., author
Stanley Thornes, 1986
Buku Teks
edited Jeffrey Jowell and Dawn Oliver
Clarendon Press, 1989
Buku Teks
edited by Jeffrey Jowell and Dawn Oliver
Clarendon Press, 1994
Buku Teks
Policy, alternatives for the Carribean and central America
Institute Studies, 1984
Buku Teks
edited by Barrie Evans, James A. Powell and Reg Talbot
Wiley, 1982
Buku Teks SO