APA (7th ed.) Citation

Kroll, C., Friedland, J., Kessler, R., & Tolkien, J. R. R. (1992). The hobbit, J.R.R. Tolkien: A study guide. Learning Links Inc..

Chicago Style (17th ed.) Citation

Kroll, Carol, Joyce Friedland, Rikki Kessler, and J. R. R. Tolkien. The Hobbit, J.R.R. Tolkien: A Study Guide. New York: Learning Links Inc., 1992.

MLA (8th ed.) Citation

Kroll, Carol, et al. The Hobbit, J.R.R. Tolkien: A Study Guide. Learning Links Inc., 1992.