@article{10_14708_dm_v12i01_6840,
     author = {. Redakcja},
     title = {Przedmowa},
     journal = {Didactica Mathematicae},
     pages = { 5},
     publisher = {mathdoc},
     volume = {12},
     number = {01},
     year = {1990},
     doi = {10.14708/dm.v12i01.6840},
     language = {pl},
     url = {http://geodesic.mathdoc.fr/articles/10.14708/dm.v12i01.6840/}
}