1981. Phylogenetics. The principles and practice of phylogenetic systematics. John 
Wiley & Sons, New York. 
~----------- , D. Siegel-Causey, D. R. Brooks & V. A. Funk. 1991. The compleat cladist. A primer 
of phylogenetic procedures. Museum of Natural History, The University of Kansas, 
Lawrence, Kansas. 
Wilkinson, H. P.1979. The plant surface (mainly leaf). in C. R. Metcalfe & L. Chalk (eds.) 
Anatomy of the dicotyledons. Vol. I. Oxford University Press, New York. pp. 97-165. 
258 
