has been called one of the best-known literary characters in the world. In addition to more than two dozen books by Burroughs and a handful more by authors with the blessing of Burroughs's estate, the character has appeared in films, radio, television, comic strips, and comic books. Numerous parodies and pirated works have also appeared. Critical reception While Tarzan of the Apes met with some critical success, subsequent books in the series received a cooler reception and have been criticized for being derivative and formulaic. The characters are often said to be two-dimensional, the dialogue wooden, and the storytelling devices (such as excessive reliance on coincidence) strain credulity. According to Rudyard Kipling (who himself wrote stories of a feral child, The Jungle Books Mowgli), Burroughs wrote Tarzan of the Apes just so he could "find out how bad a book he could write and get away with it." While Burroughs was not a polished novelist, he was a vivid storyteller. Most of his novels are still in print. In 1963, author Gore Vidal wrote a piece on the Tarzan series that, while pointing out several of the deficiencies that the Tarzan books have as works of literature, praises Burroughs for creating a compelling "daydream figure." Critical reception grew more positive with the 1981 study by Erling B. Holtsmark, Tarzan and Tradition: Classical Myth in Popular Literature. Holtsmark added a volume on Burroughs for Twayne's United States Author Series in 1986. In 2010, Stan Galloway provided a sustained study of the adolescent period of the fictional Tarzan's life in The Teenage Tarzan. Despite critical panning, the Tarzan stories have remained popular. Burroughs's melodramatic situations and the elaborate details he works into his fictional world, such as his construction of a partial language for his great apes, appeal to a worldwide fan base. Unauthorized works After Burroughs's death, a number of writers produced new Tarzan stories. In some instances, the estate managed to prevent publication of such works. The most notable example in the United States was a series of five novels by the pseudonymous "Barton Werper" that appeared 1964–65 by Gold Star Books (part of Charlton Comics). As a result of legal action by Edgar Rice Burroughs, Inc., they were taken off the market. Similar series appeared in other countries, notably Argentina, Israel, and some Arab countries. Modern fiction In 1972, science-fiction author Philip José Farmer wrote Tarzan Alive, a biography