CHAPOVSKY, Yu.; KALYUZHNYI, A. A. Factorization of Conditional Expectations on Kac Algebras and Quantum Double Coset Hypergroups. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 55, n. 12, p. 1669–1677, 2003. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/4029. Acesso em: 5 dec. 2025.