Industrial Research and Development Expenditures: Determinants, Prospects, and Relation to Size of Firm and Inventive Output Edwin Mansfield Journal of Political Economy 1964 72(4), 319-340
Size of Firm, Market Structure, and Innovation Edwin Mansfield Journal of Political Economy 1963 71(6), 556-576
The Measurement of Wage Differentials Edwin Mansfield Journal of Political Economy 1954 62(4), 346-347