Flora of North America: North of Mexico, Volume 25: Magnoliophyta: Commelinidae (in part): Poaceae, part 2 (Flora of North America, Vol. 25)
Volume 25 of the Flora of North America treats six subfamilies of the Poaceae: the Panicoideae, Arundinoideae, Chloridoideae, Centothecoideae, Aristidoideae, and Danthonioideae. Together these six subfamilies constitute the PACCAD group of grasses.