@article{JRAM_1978__297_151947,
     author = {S.V.R. Naidu and K.P.R. Sastry},
     title = {Convexity conditions in normed linear spaces.},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {35--53},
     publisher = {mathdoc},
     volume = {297},
     year = {1978},
     zbl = {0364.46009},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1978__297_151947/}
}