1. Bianucci, D., Cattaneo, G., Ciucci, D.: Entropies and co-entropies of coverings with application to incomplete information systems. Fundamenta Informaticae 75, 77–105 (2007)
2. Cattanio, G., Cucci, D.: Lattice Properties of Preclusive and Classical Rough Sets. Personal Collection
3. LNAI;M.K. Chakraborty,2007
4. Klir, G.J., Yuan, B.: Fuzzy Sets And Fuzzy Logic: Theory and Applications. Prentice-Hall of India, Englewood Cliffs (1997)
5. Lecture Notes in Computer Science;N.T. Nguyen,2004