Key points are not available for this paper at this time.
Grass Phylogeny Working Group, Nigel P. Barker, Lynn G. Clark, Jerrold I. Davis, Melvin R. Duvall, Gerald F. Guala, Catherine Hsiao, Elizabeth A. Kellogg, H. Peter Linder, Roberta J. Mason-Gamer, Sarah Y. Mathews, Mark P. Simmons, Robert J. Soreng, Russell E. Spangler, Phylogeny and Subfamilial Classification of the Grasses (Poaceae), Annals of the Missouri Botanical Garden, Vol. 88, No. 3 (Summer, 2001), pp. 373-457
Group et al. (Mon,) studied this question.