How many movies have Bobby E. Lüthge and Otto Gebühr collaborated on?

They have worked on 10 movies together! Their first movie together was Das Mädchen aus der Ackerstraße. 1. Teil (1920) while their highest rated movie together was The Heath Is Green (1951). They have not worked together since Red Roses, Red Lips, Red Wine (1953). They are most known for their drama films together.