To the 70th anniversary of birthday of Prof. Nečas Nečasová, Š. , Hana Petzeltová, Milan Pokorný, Adélia Sequeira (2001) Mathematica Bohemica
To the sixtieth anniversary of birthday of Professor Marko Švec, DrSc. Jaroslav Kurzweil (1980) Czechoslovak Mathematical Journal
To the sixtieth anniversary of birthday of Professor Otto Vejvoda Jaroslav Kurzweil, Vladimír Lovicar (1982) Czechoslovak Mathematical Journal