R. J.  Soreng and Davis, J. I., ?Phylogenetic Structure in Poaceae Subfamily Pooideae as inferred from Molecular and Morphological Characters: Misclassification versus Reticulation?, in Grasses, Systematics and Evolution, S. W. L.  Jacobs and Everett, J., Eds. Collingwood: CSIRO Publishing, 2000, pp. 61-74.

L. A.  McDade, ?Hybridization and Phylogenetics?, in Phylogenetic Analysis of Morphological Data, J. J.  Wiens, Ed. Washington DC: Smithsonian Institution Press, 2000, pp. 146-163.