5Colin A. Carter, Donald MacLaren. Price or Quantity Competition? Oli- gopolistie Structures in International Commodity Markets[J]. Review of In- ternational Economics, 1997 (8): 373-385.
6Colin A. Carter, Donald MacLaren, Alper Yilmaz. How Competitive is the World Wheat Market, Working Paper[J]. Department of Agricultural and Resource Economics, University of California Davis, 1999(7).
7LERNER A. The Concept of monopoly and the meas- urement of monopoly power[J]. Review of Economic Studies , 1934(7):157-175.
8COLIN A CARTER, DONALD MACLAREN. Price or quantity competition? Oligopolistic structures in international commodity markets[J]. Review of International Economics, 1997 (8) : 373-385.
9COLIN A CARTER , DONALD MACLARENK, ALPEER YILMAQ, How competitive is the world wheat market [J]. Working paper, 1999(7) : 38.
10CARTER C A, MACLAREN D, YILMAZ A. How competitive is the world wheat market: Working Paper No. 99-002[Z]. Department of Agricultural and Resource Economics, University of California Davis, 1999.