APA (7th ed.) Citation

Cox, E. H. M., & Cox, P. A. (1956). Modern Rhododendrons. Nelson.

Chicago Style (17th ed.) Citation

Cox, E H M., and P. A. Cox. Modern Rhododendrons. London [u.a.]: Nelson, 1956.

MLA (9th ed.) Citation

Cox, E H M., and P. A. Cox. Modern Rhododendrons. Nelson, 1956.