Куринной, Г.Ч.Невмержицкая, Е.Н.Шугайло, Е.А.2015-06-052015-06-052015-06-05https://ekhnuir.karazin.ua/handle/123456789/10638ukResearch Subject Categories::MATHEMATICS::Algebra, geometry and mathematical analysis::Algebra and geometryWorking Paper