Rinkitink in Oz
by L. Frank Baum
Prince Inga of Pingar and King Rinkitink and their friends have adventures that lead to the land of the Noms and eventually to the land of Oz. When all the inhabitants of Pingari are kidnapped by the immaculate armies of the twin island kingdoms, Prince Inga and his friend King Rinkitink decide to go to the rescue. Baum introduced the male protagonist, Prince Ingu of Pingari, to the Oz series to celebrate the birth of his grandson.
