APA (7th ed.) Citation

Riordan, R. (2016). Hotel Valhalla guide to the Norse worlds: An official Magnus Chase companion book. Puffin.

Chicago Style (17th ed.) Citation

Riordan, Rick. Hotel Valhalla Guide to the Norse Worlds: An Official Magnus Chase Companion Book. London: Puffin, 2016.

MLA (8th ed.) Citation

Riordan, Rick. Hotel Valhalla Guide to the Norse Worlds: An Official Magnus Chase Companion Book. Puffin, 2016.

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