@article{GDZPPN002301431, title = {Optimization Theory in Linear Spaces. I.}, journal = {Mathematische Annalen}, volume = {180}, year = {1969}, pages = {189-206}, zbl = {0177.40402}, url = {http://dml.mathdoc.fr/item/GDZPPN002301431} }
RITTER, K. Optimization Theory in Linear Spaces. I.. Mathematische Annalen, Tome 180 (1969) pp. 189-206. http://gdmltest.u-ga.fr/item/GDZPPN002301431/