6Wen Jen Hsieh.Test of variable output and scale elasticities for 20 US manufacturing industries [J].Applied Economics Letters, 1995.
7Biresh Kumar Sahoo. A comarative ap. plication of data envelopment analysis and frontier translog production function for estimating returns to scale and efficiencies[J].International journal of systems science, 1999.
8Fare.A note on Ray-homogeneous and Ray-homothetic produciton functions [J].Swed of Economics, 1975.
