On dense subsets of rational numbers Jacek Cichoń — 2001 Acta Universitatis Carolinae. Mathematica et Physica
On almost invariant subsets of the real line Jacek Cichoń; Przemyslaw Szczepaniak — 2001 Acta Universitatis Carolinae. Mathematica et Physica
A note on complex unions of subsets of the real line Jacek Cichoń; Andrzej Jasiński — 2001 Acta Universitatis Carolinae. Mathematica et Physica
On the splitting number and Mazurkiewicz's theorem Jacek Cichoń; Szymon Żeberski — 2001 Acta Universitatis Carolinae. Mathematica et Physica
Some applications of strong Lusin sets Jan Brzuchowski; Jacek Cichoń; Bogdan Weglorz — 1981 Compositio Mathematica
Dualization of van Douwen diagram Jacek Cichoń; Barbara Majcher-Iwanow; Bogdan Węglorz — 1992 Acta Universitatis Carolinae. Mathematica et Physica