00513naa#a2200181#i#450# EN\INFRA-M\bibl\7976 20250123233114.4 2308-4898 20151130b2015####ek#y0engy0150####ca RUS RU Graphical Proof of the Main Theorem of Non-Euclidean Geometry Journal article Moscow INFRA-M Academic Publishing LLC. 2015 5 с. Journal article local Safiulina Yu. Shmurnov V. zh-szf.ru