1. Le bassin versant de Roujan;Andrieux,1993
2. Pattern Recognition with Fuzzy Objective Function Algorithms;Bezdek,1981
3. Carte Géologique de la France au 1: 50.000, Feuille de Pézenas;BRGM,1983
4. Fuzzy mathematical methods for soil survey and land evaluation;Burrough;J. Soil Sci.,1989
5. Continuous classification in soil survey: spatial correlation, confusion and boundaries;Burrough,1997