Business, trade and economic progress in cambodia Shri H.M. Mahatni
 Artikel Jurnal
Beard, Charles A.
The Making of American civilization
Macmillan, 1948
 Buku Teks
Moulton, Harold G.
Income and economic progress
Brookings Institution, 1935
 Buku Teks
Readings in business cycle theory / selected by a Committee of the American economic association
George Allen & Unwin Ltd, 1951
 Buku Teks
Banerji, Hrishikes
Technical progress and the process of economic development
Universities Foundation, 1956
 Buku Teks