@article{AM2_1993__46_2-3_137544,
     author = {Pl. Kannappan and K. Baron},
     title = {On the {Cauchy} difference.},
     journal = {Aequationes mathematicae},
     pages = {112--118},
     year = {1993},
     volume = {46},
     number = {2-3},
     zbl = {0796.39011},
     url = {http://geodesic.mathdoc.fr/item/AM2_1993__46_2-3_137544/}
}