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..
Eric Shanower
Shanower's first major published works were the "Oz" graphic novels, which are "The Enchanted Apples of Oz", "The Secret Island of Oz", "The Ice King of Oz", "The Forgotten Forest of Oz", and "The Blue Witch of Oz" released by First Comics and Dark Horse Comics between 1986 and 1992. They are collected in a single large volume titled "Adventures in Oz", published by IDW.