How many movies have Oldřich Velen and Vladimír Hovorka collaborated on?

They have worked on 4 movies together! Their first movie together was A Valley of Beautiful Frogs (1974) while their highest rated movie together was Sedmého dne večer (1975). They have not worked together since Skandál v Gri-Gri baru (1979). They are most known for their drama films together.