The Wizard of Oz (1902 musical)
The Wizard of Oz was a 1902 musical extravaganza based on "The Wonderful Wizard of Oz" by L. Frank Baum, which was originally published in 1900. Much of the original music was by Paul Tietjens and has been mostly forgotten, although it was still well-remembered and in discussion at MGM in 1939 when the classic film version of the story was made. Although Baum is the credited bookwriter, Glen MacDonough was hired on as jokewriter after Baum had finished the script.
Copyright status of The Wizard of Oz and related works in the United States
The McGraws co-wrote another Oz book, "The Forbidden Fountain of Oz", which was published in 1980. Its copyright lasts for seventy years after the death of last living author. Lauren McGraw is still alive, so "The Forbidden Fountain of Oz" will enter the public domain seventy years after her death. Since it will remain copyrighted until at least 2085, it will be the last deutero-canonical work to enter the public domain.