@article{MAN_1978__236_163166,
     author = {Charles Stegall},
     title = {Optimization of {Functions} on {Certain} {Subsets} of {Banach} {Spaces.}},
     journal = {Mathematische Annalen},
     pages = {171--176},
     publisher = {mathdoc},
     volume = {236},
     year = {1978},
     zbl = {0365.49006},
     url = {http://geodesic.mathdoc.fr/item/MAN_1978__236_163166/}
}