@article{10_14708_wm_v13i1_2018,
     author = {A. Waszak},
     title = {A. {Sobotka} {Elementy} matematyki wy\.zszej},
     journal = {Wiadomo\'sci Matematyczne},
     pages = { 148--151},
     publisher = {mathdoc},
     volume = {13},
     number = {1},
     year = {1971},
     doi = {10.14708/wm.v13i1.2018},
     language = {pl},
     url = {http://geodesic.mathdoc.fr/articles/10.14708/wm.v13i1.2018/}
}