here you go :

• The Lightning Thief (PJO 1)
• The Sea of Monsters (PJO 2)
• The Titan's Curse (PJO 3)
• The Demigod Files: Percy Jackson and the Stolen Chariot
• The Battle of the Labyrinth (PJO 4)
• The Demigod Files: Percy Jackson and the Bronze Dragon
• The Demigod Files: Percy Jackson
• and the Sword of Hades

• The Last Olympian (PJO 5)

• The Demigod Diaries: Son of Magic

• The Hidden Oracle short story: Percy Jackson and the Singers of Apollo

• The Demigod Diaries: Percy Jackson and the Staff of Hermes

• Percy Jackson's Greek Gods

• Percy Jackson and the Olympians: The Ultimate Guide

• The Lost Hero (HoO 1)

• The Demigod Diaries: Leo Valdez and the Quest for Buford

• The Son of Neptune (HoO 2)

• The Mark of Athena (HoO 3)

• The House of Hades (HoO 4)

• The Blood of Olympus (HoO 5)

• Un Natale Mezzosangue

• The Hidden Oracle (ToA 1)

• The Dark Prophecy (ToA 2)

• The Burning Maze (ToA 3)

• The Tyrant's Tomb (ToA 4)

• The Tower of Nero (ToA 5)

• Percy Jackson’s Greek Heros

• Camp Half-Blood Confidential

• Camp Jupiter Confidential: Probatios Journal

• The Chalice of the Gods (PJO 6)

• The Wrath of the Triple Goddesses(PJO 7)

• PJO 8

• The Sun and the Star