#13 TARZAN AT THE EARTH'S CORE                                       #14 TARZAN THE INVINCIBLE                                                   #15 TARZAN TRIUMPHANT                                                  #22 TARZAN AND "THE FOREIGN LEGION"                             by Edgar Rice Burroughs                                                              Ballantine Books, First Authorized Paperback Printings, 1964     Condition: Near Very Good                                                                                                                                                                These four books, along with six other Tarzan titles, were simultaneously published by Ballantine Books, the first authorized paperback printings, in March 1964.  #13 has a reading crease, modest spine edge wear and a store stamp inside; #14 has some cover corner and edge wear; #15 has a short closed split at bottom of spine and back cover creasing; #22 has a  spine lean and some general exterior wear.  All are securely bound with no pencil or ink markings observed.