@article{10_14708_wm_v5i1_2892,
     author = {J. Mikusi\'nski},
     title = {O czworo\'scianie},
     journal = {Wiadomo\'sci Matematyczne},
     pages = { 39--42},
     publisher = {mathdoc},
     volume = {5},
     number = {1},
     year = {1962},
     doi = {10.14708/wm.v5i1.2892},
     language = {pl},
     url = {http://geodesic.mathdoc.fr/articles/10.14708/wm.v5i1.2892/}
}