ATTI DEL SEMINARIO MATEMATICO E FISICO DELL'UNIVERSITA' DI MODENA
Abstract
This paper is about the structure of the core of the A-hypergroups. We prove that in some A-hypergroups the core is equal to a hyperaddition of zero type and we give another example that shows the existence of some A-hypergroups for which that property is not true. Finally, using Zorn's lemma, we prove some theorems about the extension of canonical hypergroups and A-hypergroups.
