How many movies have Frank Welker and Gil Iverson collaborated on?

They have worked on 4 movies together! Their first movie together was Yogi Bear and the Magical Flight of the Spruce Goose (1987) while their highest rated movie together was Scooby-Doo and the Ghoul School (1988). They have not worked together since Jetsons: The Movie (1990). They are most known for their animation films together.