9Coelli, T.J. , Rao, D. S. P. , O1)onnell, C.J. & Bat- tese, G.E. An introduction to efficiency and produc- tivity analysis. Springer, 2005.
10De Borger B, Kerstens K. Cost efficiency of Belgian local governments: A comparative analysis of FDH, DEA, and econometric approaches [ J ]. Regional Sci- ence and Urban Economics, 1996, 26 (02) : 145-170.