%0 Journal Article %A Josef Šlapal %T A closure operator for the digital plane %J Filomat %D 2020 %P 3229 %V 34 %N 10 %U http://geodesic.mathdoc.fr/articles/10.2298/FIL2010229S/ %R 10.2298/FIL2010229S %G en %F 10_2298_FIL2010229S