@article{MV_1975_27_1_a27,
     author = {S. Czerwik},
     title = {Continuous solutions of a functional equation},
     journal = {Matemati\v{c}ki vesnik},
     pages = {241 },
     publisher = {mathdoc},
     volume = {27},
     number = {1},
     year = {1975},
     url = {http://geodesic.mathdoc.fr/item/MV_1975_27_1_a27/}
}