@article{AM2_1972__8_136295,
     author = {J. Matkowski},
     title = {The {Uniqueness} of {Solutions} of a {System} of {Functional} {Equations} in {Some} {Classes} of {Functions.}},
     journal = {Aequationes mathematicae},
     pages = {233--237},
     publisher = {mathdoc},
     volume = {8},
     year = {1972},
     zbl = {0253.39013},
     url = {http://geodesic.mathdoc.fr/item/AM2_1972__8_136295/}
}