Répertoire des noms génériques mentionnés dans l'Index kewensis et ses quinze premiers suppléments = Guide to the generic names appearing in the Index Kewensis and its fifteen supplements = Repertorio de los nombres genericos enumerados en el Index Kewensis y sus quince suplementos = Repertorium der im Index Kewensis und seinen fuenfzehn ersten Supplementen erwaehnten Gattungsnamen - Rouleau, Ernest 1916 -1991 (Châtelain, 1981)

Report / Botanical Society and Exchange Club of the British Isles - Botanical Society; Exchange Club of the British Isles. (1916)

Reports of the Survey. Botanical series - Geological; Natural History Survey of Minnesota. (1892)

Reproductive ecology of Conradina verticillata Jennison, a rare, endemic mint of the Cumberland Plateau - Roulston, T'ai Honda. (1994)

Western Australian Herbarium Research Notes - Western Australia. Department of Biodiversity, Conservation; Attractions (Western Australian Herbarium, 1979)

Western Australian Herbarium Research Notes - Western Australia. Department of Biodiversity, Conservation; Attractions (Western Australian Herbarium, 1980)

Western Australian Herbarium Research Notes - Western Australia. Department of Biodiversity, Conservation; Attractions (Western Australian Herbarium, 1981)

Western Australian Herbarium Research Notes - Western Australia. Department of Biodiversity, Conservation; Attractions (Western Australian Herbarium, 1983)

Restoration guidelines for wetlands of the western Prairie Pothole Region - United States. Environmental Protection Agency. (Montana Natural Heritage Program, 2012)

Restoration of sand prairie in Illinois : seed banks and existing vegetation June 2005-2006 final report - Illinois. Department of Natural Resources. (Illinois Natural History Survey, 2007)

Review of North American Chlamydatus Curtis species, with new synonymy and the description of two new species (Heteroptera, Miridae, Phylinae) - Schuh, Randall T. (American Museum of Natural History, 2005)

Revised checklist of New York State plants - Mitchell, Richard S., 1938 - (University of the State of New York, State Education Dept, 1997)