@article{ZNSL_2012_406_a4,
     author = {G. V. Nenashev},
     title = {On a~bound on the chromatic number of almost planar graph},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {95--106},
     publisher = {mathdoc},
     volume = {406},
     year = {2012},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_2012_406_a4/}
}