APA (7th ed.) Citation

Coelho, P., & Clarke, A. R. (2007). The valkyries. Harper.

Chicago Style (17th ed.) Citation

Coelho, Paulo, and Alan R. Clarke. The Valkyries. London, England: Harper, 2007.

MLA (9th ed.) Citation

Coelho, Paulo, and Alan R. Clarke. The Valkyries. Harper, 2007.

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