APA Style
Riordan, Rick. (2012).
Heroes of Olympus: the Mark of Athena .
London:
Puffin.
Chicago Style
Riordan, Rick.
Heroes of Olympus: the Mark of Athena.
London:
Puffin,
2012.
Text.
MLA Style
Riordan, Rick.
Heroes of Olympus: the Mark of Athena.
London:
Puffin,
2012.
Text.
Turabian Style
Riordan, Rick.
Heroes of Olympus: the Mark of Athena.
London:
Puffin,
2012.
Print.