@article{10_14708_wm_v7i2_2357,
     author = {H. Steinhaus},
     title = {O r\'ownowadze oboj\k{e}tnej},
     journal = {Wiadomo\'sci Matematyczne},
     pages = { 215--220},
     publisher = {mathdoc},
     volume = {7},
     number = {2},
     year = {1964},
     doi = {10.14708/wm.v7i2.2357},
     language = {pl},
     url = {http://geodesic.mathdoc.fr/articles/10.14708/wm.v7i2.2357/}
}