Portela MCAS and E Thanassoulis (2004). “Malmquist Indexes Using a Geometric Distance Function (GDF).” in Emrouznejad A and V Podinovski (eds.) Proceedings of DEA2004, Birmingham, UK: 229.
Portela MCAS and E Thanassoulis (2004). “Malmquist Indexes Using a Geometric Distance Function (GDF).” in Emrouznejad A and V Podinovski (eds.) Proceedings of DEA2004, Birmingham, UK: 229.