Purpose:
1. DAŇKOVÁ, M. Extensionality as a basis for fuzzy approximation. In 8th International Conference on Fuzzy Set Theory an Applications FSTA'06. 30.1.-3.2. Liptovský Ján, Slovensko. Liptovský Mikuláš, Slovensko : Academy of Armed Forces of General M.R. Štefánik in Liptovský Mikuláš, 2006. s. 34-34. ISBN 80-8040-284-1.
2. DAŇKOVÁ, M., BĚHOUNEK, L. Relation Compositions in Fuzzy Class Theory. In 8th International Conference on Fuzzy Set Theory an Applications FSTA'06. 30.1.-3.2. Liptovský Ján, Slovensko. Liptovský Mikuláš, Slovensko : Academy of Armed Forces of General M.R. Štefánik in Liptovský Mikuláš, 2006. s. 23-23. ISBN 80-8040-284-1.