Author: Eloise Jarvis McGraw
McGRAW, Eloise Jarvis. The Forbidden Fountain of Oz by Eloise Jarvis McGraw & Lauren Lynn McGraw. Illustrated by Dick Martin. [Kinderhook, IL]: The International Wizard of Oz Club, Inc. . 4to, 99pp +  advts. Color pictorial paper wrappers. Illustrations in b&w throughout. As new, in shrink-wrap, as issued. This paperback edition is no longer in print. The book is only available for purchase as a $25 hardcover.
Second printing, issued 10 years after the 1st printing, having advts. at rear of volume dated 1990. The authors of Merry Go Round in Oz, Newbery Honor author Eloise Jarvis McGraw and her daughter, return to the land of Oz. When Ozma accidentally drinks from the Forbidden Fountain and forgets that she is the true ruler of Oz, a series of breathtaking adventures ensue, and it’s up to Kabumpo to help his friend regain her memory and retake her throne.