Although uncredited, Dennis Marks, along with Jack Mendelsohn, Heywood Kling and Bruce Howard, wrote all 39 episodes of The Beatles series [REF].
Most of the episodes of the series were produced by Artransa Park Studios in Sydney, New South Wales, Australia[REF] and George Dunning's company TVC Animation in London,[REF] with a handful of episodes made in Hollywood,[REF] with a crew supervised by veteran cartoon writer John W. Dunn [REF].