@article{10_14708_cm_v29i1_6250,
     author = {E. Ambro\.zko},
     title = {On modular filters},
     journal = {Commentationes Mathematicae},
     pages = { 1--21},
     publisher = {mathdoc},
     volume = {29},
     number = {1},
     year = {1989},
     doi = {10.14708/cm.v29i1.6250},
     language = {pl},
     url = {http://geodesic.mathdoc.fr/articles/10.14708/cm.v29i1.6250/}
}