L. Frank Baum (2013). “Oz, the Complete Collection, Volume 4: Rinkitink in Oz; The Lost Princess of Oz; The Tin Woodman of Oz”, p.157, Simon and Schuster
L. Frank Baum (2013). “Oz, the Complete Collection, Volume 1: The Wonderful Wizard of Oz; The Marvelous Land of Oz; Ozma of Oz”, p.36, Simon and Schuster