APA (7th ed.) Citation

Burrell, C. C., & Tyler, J. K. (2006). Hellebores: A comprehensive guide. Timber Press.

Chicago Style (17th ed.) Citation

Burrell, C. Colston, and Judith Knott Tyler. Hellebores: A Comprehensive Guide. Portland, Or: Timber Press, 2006.

MLA (9th ed.) Citation

Burrell, C. Colston, and Judith Knott Tyler. Hellebores: A Comprehensive Guide. Timber Press, 2006.