@article{RM_1985_40_4_a21,
     author = {V. D. Batukhtin},
     title = {On the problem of the extremum of discontinuous maps},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     pages = {157--158},
     publisher = {mathdoc},
     volume = {40},
     number = {4},
     year = {1985},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/RM_1985_40_4_a21/}
}