On isotropy group of Danielewski surfaces

Isotropy subgroups of some almost rigid domains

“…Moreover, the question looks interesting for almost rigid domains (see Definition 2.2), where every locally nilpotent derivation is a replica of a canonical one. R. Baltazar and M. Veloso ( [3]) have studied this question for certain types of Danielewski surfaces, which are examples of almost rigid domains. In fact, they have described the isotropy subgroups of locally nilpotent derivations on Danielewski surfaces defined by equations of the form f (X)Y − P (Z) over an algebraically closed field of characteristic zero.…”