@article{10_14708_wm_v28i02_4458,
     author = {A. Tyszka},
     title = {Zadania},
     journal = {Wiadomo\'sci Matematyczne},
     pages = { 259--260},
     publisher = {mathdoc},
     volume = {28},
     number = {02},
     year = {1990},
     doi = {10.14708/wm.v28i02.4458},
     language = {pl},
     url = {http://geodesic.mathdoc.fr/articles/10.14708/wm.v28i02.4458/}
}