@misc{WM_1900_4_1-2-3_a2,
     title = {Z teoryi u{\l}amk\'ow ci\k{a}g{\l}ych},
     journal = {Wiadomo\'sci Matematyczne},
     pages = {52--59},
     publisher = {mathdoc},
     volume = {4},
     number = {1-2-3},
     year = {1900},
     language = {pl},
     url = {http://geodesic.mathdoc.fr/item/WM_1900_4_1-2-3_a2/}
}