ArticleIssue Date2019CitationProceedings of the Jangjeon Mathematical Society, v.22, no.3, pp 487 - 497PublisherJangjeon Research Institute for Mathematical Sciences and Physics
ArticleIssue Date2019CitationProceedings of the Japan Academy Series A: Mathematical Sciences, v.95, no.3, pp 24 - 29PublisherNippon Gakushiin/Japan Academy