APA (7th ed.) Citation

Riordan, R. (2015). Heroes of Olympus: The son of neptune. Puffin Books.

Chicago Style (17th ed.) Citation

Riordan, Rick. Heroes of Olympus: The Son of Neptune. UK: Puffin Books, 2015.

MLA (9th ed.) Citation

Riordan, Rick. Heroes of Olympus: The Son of Neptune. Puffin Books, 2015.

Warning: These citations may not always be 100% accurate.