@article{AM2_1989__38_1_137322,
     author = {John S. Lew},
     title = {A functional equation of {Ih-Ching} {Hsu.}},
     journal = {Aequationes mathematicae},
     pages = {146--154},
     publisher = {mathdoc},
     volume = {38},
     number = {1},
     year = {1989},
     zbl = {0687.39007},
     url = {http://geodesic.mathdoc.fr/item/AM2_1989__38_1_137322/}
}