@article{AM2_1992__43_1_137464,
     author = {H.L. Vasudeva and J.C. Parnami},
     title = {On {Jensen's} functional equation.},
     journal = {Aequationes mathematicae},
     pages = {211--218},
     publisher = {mathdoc},
     volume = {43},
     number = {1},
     year = {1992},
     zbl = {0755.39008},
     url = {http://geodesic.mathdoc.fr/item/AM2_1992__43_1_137464/}
}