APA (7th ed.) Citation

Gaarder, J., Hails, S. J., & Kramer, H. (1997). The solitaire mystery. Phoenix House.

Chicago Style (17th ed.) Citation

Gaarder, Jostein, Sarah Jane Hails, and Hilda Kramer. The Solitaire Mystery. London, England: Phoenix House, 1997.

MLA (9th ed.) Citation

Gaarder, Jostein, et al. The Solitaire Mystery. Phoenix House, 1997.