@article{MZM_1970_7_6_a1,
     author = {L. S. Mel'nikov},
     title = {The chromatic class and the location of a graph on a closed surface},
     journal = {Matemati\v{c}eskie zametki},
     pages = {671--682},
     publisher = {mathdoc},
     volume = {7},
     number = {6},
     year = {1970},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1970_7_6_a1/}
}