The Tarzan books have been in continuous publication since 1912.
“The Return of Tarzan is the second book in the series. http://www.amazon.com...The Return of Tarzan
“Tarzan, Lord of the Jungle is the 11th Tarzan novel by Edgar Rice Burroughs. It was serialized...Tarzan, Lord of the Jungle
“The Beasts of Tarzan is the third book in the series. http://www.amazon.com...The Beasts of Tarzan
“by Edgar Rice Burroughs Tarzan of the Apes (1912) (Project Gutenberg Entry:), The Return of...Books