00480naa#a2200169#i#450# EN\INFRA-M\bibl\35506 20240418232941.4 2308-4898 20191225b2019####ek#y0engy0150####ca RU New Problems of Descriptive Geometry Journal article Moscow INFRA-M Academic Publishing LLC. 2019 15 с. Journal article local Математика. 51 Girsh A. G. riorpub.com