B. Blackwell for the United Nations Industrial Development Organization, 1991
Buku Teks
The World Bank, 1995
Buku Teks
Lavigne, Marie
Macmillan Press , 1995
Buku Teks
Montias, John Michael
Yale University Press, 1962
Buku Teks
Karpinski, Andrzej, author
Polonia Publishing House, 1964
Buku Teks