@article{YJOR_1991_1_1_a0,
     author = {Sanjo Zlobec},
     title = {Characterizing {Optimality}  in {Nonconvex} {Optimizationi}},
     journal = {Yugoslav journal of operations research},
     pages = {3 },
     publisher = {mathdoc},
     volume = {1},
     number = {1},
     year = {1991},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/YJOR_1991_1_1_a0/}
}