1. Pseudometrics associated with fuzzy relations having weak properties;Burillo,1989
2. Fuzzy relational spaces;Caire;Rend. Sem. Mat. Univ. Cagliari,1977
3. Extending fuzzy relations;González;Fuzzy Sets and Systems,1995
4. General Topology;Kelley,1955
5. Equality relations as a basis for fuzzy control;Klawonn;Fuzzy Sets and Systems,1993