^Peter H., et al. Raven (2012). 9780716762843, W.H. Freeman. ISBN 9780716762843 (revised Jan 2014)
^Peter H. Raven, Ray F. Evert, Susan E. EichhornBiology of Plants by Ray F. Evert, Susan E. Eichhorn and Peter H. Raven (2005, Quantity pack)ISBN 9780716762843 (revised Mar 2015)