00521naa#a2200181#i#450# EN\INFRA-M\bibl\11982 /en/manage/index 20250410155500.4 2308-4898 20160618b2016####ek#y0engy0150####ca RUS RU Dupin Cyclide and Second-Order Curves. Part 1 Journal article Moscow INFRA-M Academic Publishing LLC. 2016 9 с. Journal article local Sal'kov N. A. test.editorum.ru /en/manage/index