General form of the automorphism group of bicyclic graphs

In 1869, Jordan proved that the set T of all finite groups that can be represented as the automorphism group of a tree is containing the trivial group, it is closed under taken the direct product of groups of lower orders in T , and wreath product of a member of T and the symmetric group on n symbols is again an element of T . The aim of this paper is to continue this work and another works by Klavik and Zeman in 2017 to present a class S of finite groups for which the automorphism group of each bicyclic graph is a member of S and this class is minimal with this property.