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Advertising and competition : theory, measurement, fact
Ferguson, James Milton, (1974)
Measuring entry barriers using a switching regression model of industry profitability
Chappell jr., Henry W., (1983)
Big business, efficiency and fascism : an appraisal of the efficiency of large corporations and of their threat to democracy
Simpson, Kemper, (1941)
Concentration, barriers to entry, and long run economic profit margins
Qualls, David, (1972)
Price stability in concentrated industries
Qualls, David, (1975)
Concentration, Barriers to Entry, and Long Run Economic Profit Margins.