@article{TDM_2004_8_a14,
     author = {N. D. Podufalov},
     title = {On some characterizations of exponential functions on linear spaces},
     journal = {Trudy po diskretnoj matematike},
     pages = {216--239},
     publisher = {mathdoc},
     volume = {8},
     year = {2004},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TDM_2004_8_a14/}
}