Who wrote the screenplay for the film in which Mark Lester played the title role?
Mark Lester: Mark Lester (born Mark A. Letzer; 11 July 1958) is an English former child actor known for playing the title role in the 1968 musical film version of "Oliver! Oliver! (film): Oliver! Oliver! (film):  is a 1968 British musical drama film directed by Carol Reed and based on the stage musical of the same name, with book, music and lyrics written by Lionel Bart. Oliver! (film):  The screenplay was written by Vernon Harris.
Vernon Harris