APA (7th ed.) Citation

Cullen, J. (2005). Hardy rhododendron species: A guide to identification. Timber Press.

Chicago Style (17th ed.) Citation

Cullen, James. Hardy Rhododendron Species: A Guide to Identification. Portland, Or: Timber Press, 2005.

MLA (9th ed.) Citation

Cullen, James. Hardy Rhododendron Species: A Guide to Identification. Timber Press, 2005.

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