At the Earth's Core
Edgar Rice Burroughs
Pellucidar (1)
Pellucidar
Pellucidar (2)
Tanar of Pellucidar
Pellucidar (3)
Back to the Stone Age
Pellucidar (5)
Land of Terror
Pellucidar (6)
Savage Pellucidar
Pellucidar (7)