How many movies have Siegfried Zügel and Wolfgang Bellenbaum collaborated on?

They have worked on 4 movies together! Their first movie together was Love Games People Play in Denmark (1971) while their highest rated movie together was School for Swingers (1973). They have not worked together since Ob Dirndl oder Lederhose - gejodelt wird ganz wild drauflos (1974). They are most known for their comedy films together.