TY  - JOUR
AU  - G. V. Nenashev
TI  - On Heawood-type problem for maps with tangencies
JO  - Zapiski Nauchnykh Seminarov POMI
PY  - 2014
SP  - 74
EP  - 88
VL  - 427
UR  - http://geodesic.mathdoc.fr/item/ZNSL_2014_427_a4/
LA  - ru
ID  - ZNSL_2014_427_a4
ER  -