L. Frank Baum 
Lost Princess of Oz [EPUB ebook] 

Princess Ozma is missing! When Dorothy awakens one morning to discover that the beloved ruler of the Land of Oz has disappeared, all of the Emerald City’s most celebrated citizens join in the search for the lost princess. But Ozma isn’t all that’s gone missing. The magical treasures of Oz have disappeared, too, including the Magic Picture, the Wizard’s black bag, and even Glinda’s Great Book of Records. With no clues to guide them, Ozma’s friends separate into four search parties and spread out across their vast country in a desperate quest for their absent ruler.