@article{IVM_2003_12_a3,
     author = {V. F. Dem'yanov and F. Fakkinei},
     title = {Two-level optimization problems and penalty functions},
     journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika},
     pages = {49--61},
     publisher = {mathdoc},
     number = {12},
     year = {2003},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IVM_2003_12_a3/}
}