@article{10_14708_cm_v20i2_5906,
     author = {Z. Kare\'nska},
     title = {On some two functional equations in the theory of geometric objects},
     journal = {Commentationes Mathematicae},
     pages = { 365--375},
     publisher = {mathdoc},
     volume = {20},
     number = {2},
     year = {1978},
     doi = {10.14708/cm.v20i2.5906},
     language = {pl},
     url = {http://geodesic.mathdoc.fr/articles/10.14708/cm.v20i2.5906/}
}