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A test of static equilibrium models and rates of return to quasi-fixed factors, with an application to the Bell system
Schankerman, Mark, (1986)
Technical change, returns to scale, and the productivity slowdown
Nadiri, M. Ishaq, (1981)
Restricted cost functions and the rate of return to quasi-fixed factors, with an application to r&d and capital in the Bell system
Schankerman, Mark, (1987)