Seventieth birthday of Professor Otakar Borůvka Miloš Ráb (1969) Czechoslovak Mathematical Journal Similarity:
Academician Otakar Borůvka (on the occasion of his ninetieth birthday) (1990) Archivum Mathematicum Similarity:
Professor Michal Křížek, Editor-in-Chief of Applications of Mathematics, is sixty Karel Segeth (2012) Applications of Mathematics Similarity: