6Charnes,A., Cooper, W.W. and Rhodes, E., "Measuring the Efficiency of Decision Making Units", European Journal of Operational Research, 1978, 2, pp. 429-444.
7Farrell, M. J., "The Measurement of Productive Efficiency", Journal of the Royal Statistical Society, 1957, 120, pp. 253-281.
8F?re, R.S., Grosskopf, S. and Lovell, C.A.K. Production Frontiers. Cambridge University Press, 1994.
9Reardon,J. and Vida, I., “Measuring Retail Productivity: Monetary vs Physical Input Measures”, The International Review of Retail, Distribution and Consumer Research, 1998, 8(4), pp. 399-413.
10Dawson,J. "Output Considerations in Retail Productivity", International Review of Retail, Distribution and Consumer Research, 2005,15(3), pp. 337-349.