1. Tawfik BEN AMOR and Thuraya MELLAH. COST EFFICIENCY OF TUNISIAN WATER DISTRIBUTION UTILITIES: AN HETEROSKEDASTIC STOCHASTIC COST FRONTIER APPROACH. Journal of Economics Theory (2016 Volume 10). Vol. 10, Issue 4, Pages 1-9, 2016

2. Thuraya Mellah and Tawfik Ben Amor. Performance of the Tunisian Water Utility: An input-distance function approach. Utility plicy. Vol. 38, Issue February 2016,, Pages Pages 18–32, 2016

3. Tawfik Ben Amor and Mohamed Goaied. "Stochastic Varying Coefficient Frontier Model in the Estimation of Technical Efficiency and Technical Efficiency of Specific Input". Agricultural Journal. Vol. Vol 5, Issue 6, Pages p 329-337, 2010

4. Tawfik Ben Amor and Christophe Muller. "Application of Stochastic Production Frontier in the Estimation of Technical Efficiency of Irrigated Agriculture in Tunisia". Agricultural Journal. Vol. 5, Issue 2, Pages p50-56., 2010