Ozma of Oz: A Record of Her Adventures with Dorothy Gale of Kansas, the Yellow Hen, the Scarecrow, the Tin Woodman, Tiktok, the Cowardly Lion and the Hungry Tiger; Besides Other Good People too Numerous to Mention Faithfully Recorded Herein published on July 30, 1907, was the third book of L. Frank Baum's Oz series. It was the first in which Baum was clearly intending a series of Oz books. (Summary by Wikipedia)