Bell, A.D. 1997. Plant form: an illustrated guide to flowering plant morphology. Oxford University Press, Oxford, U.K. preview in google books (页面存档备份,存于互联网档案馆)
Bell, A.D. 1997. Plant form: an illustrated guide to flowering plant morphology. Oxford University Press, Oxford, U.K. preview in google books (页面存档备份,存于互联网档案馆)