@article{10_14708_dm_v19i01_6754,
     author = {Grzegorz Bryll and Robert Sochacki},
     title = {O dw\'och r\'o\.znych poj\k{e}ciach zbioru},
     journal = {Didactica Mathematicae},
     pages = { 5--13},
     publisher = {mathdoc},
     volume = {19},
     number = {01},
     year = {1997},
     doi = {10.14708/dm.v19i01.6754},
     language = {pl},
     url = {http://geodesic.mathdoc.fr/articles/10.14708/dm.v19i01.6754/}
}