@article{MZM_1970_7_1_a7,
     author = {V. N. Koshelev and S. F. Morozov},
     title = {Existence of discontinuous solutions for simplest semidefinite problems of variational calculus},
     journal = {Matemati\v{c}eskie zametki},
     pages = {69--78},
     publisher = {mathdoc},
     volume = {7},
     number = {1},
     year = {1970},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1970_7_1_a7/}
}