Copyright status of The Wizard of Oz and related works in the United States
"The Wonderful Wizard of Oz" was published in 1900, and was the first to enter the public domain in "1956". This allowed Reilly & Lee, the publisher of all the other Oz books (as well as Baum's other books) to issue their own edition of "The Wizard of Oz", which had previously been published by George M. Hill Company and later by the Bobbs Merill Company after Hill went bankrupt..
The Giant Garden of Oz
The Giant Garden of Oz is a novel written and illustrated by Eric Shanower, first published in 1993 by Emerald City Press, a division of Books of Wonder. As its title indicates, the novel is a volume in the ever-growing literature on the Land of Oz, written by L. Frank Baum and many successors.