The Battle of the Labyrinth
Rick Riordan
Percy Jackson and the Olympians (4)
The Last Olympian
Percy Jackson and the Olympians (5)
The Lost Hero
The Heroes of Olympus (1)
The Sea of Monsters
Percy Jackson and the Olympians (2)
Titan's Curse, the (Percy Jackson and the Olympians, Book 3)
Percy Jackson and the Olympians (3)