Rapid biological inventories - Field Museum of Natural History. Environmental; Conservation Programs. (Field Museum, 2006)

Rapid biological inventories - Field Museum of Natural History. Environmental; Conservation Programs. (Field Museum, 2007)

Rapid inventories, biological and social - Field Museum of Natural History. (Field Museum, 2008)

Rare and endangered plants of Puerto Rico : a committee report - United States. Soil Conservation Service. (U.S. Dept. of Agriculture, Soil Conservation Service in cooperation with the Department of Natural Resources, Commonwealth of Puerto Rico, 1975)

Rare and endangered vascular plant species in Massachusetts : as abridged from Coddington and Field, 1978 - Massachusetts. Dept. of Environmental Management. (Massachusetts Dept. of Environmental Management], 1979)

Rare and endemic trees of Puerto Rico and the Virgin Islands - United States. Forest Service. (U.S. Dept. of Agriculture, Forest Service, 1980)

Rare and Threatened Plants of Cuba: ex-situ conservation in Botanic gardens (1989)

Rare native plants of Massachusetts - Massachusetts. Division of Fisheries; Wildlife. (Massachusetts Division of Fisheries and Wildlife, 1987)

Rare native plants of Massachusetts - Massachusetts. Division of Fisheries; Wildlife. (Division of Fisheries and Wildlife, 1989)

Rare native plants of Massachusetts - Massachusetts. Division of Fisheries; Wildlife. (Massachusetts Division of Fisheries and Wildlife, 1985)

A rare plant survey of the Wainwright Dunes Ecological Reserve - Alberta. Alberta Sustainable Resource Development. (Alberta Sustainable Resource Development, Resource Data Branch, Public Lands Division, 2003)

Rare plants of New York State - Mitchell, Richard S., 1938 - (New York State Museum, University of the State of New York, State Education Dept, 1981)

The Reading Nursery - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Reading Nursery, 1898)

Reading Nursery [catalogue] - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Jacob W. Manning, 1907)

A record of plants collected in Southern Rhodesia; arramged on Engler's system - Eyles, Fred (1916)

Records of the Auckland Institute and Museum - Auckland Institute; Museum. (Auckland Institute and Museum, 1931)

Records of the Auckland Institute and Museum - Auckland Institute; Museum. (Auckland Institute and Museum, 1942)

Records of the Auckland Institute and Museum - Auckland Institute; Museum. (Auckland Institute and Museum, 1939)

Records of the Auckland Institute and Museum - Auckland Institute; Museum. (Auckland Institute and Museum, 1948)

Records of the Auckland Institute and Museum - Auckland Institute; Museum. (Auckland Institute and Museum, 1970)

Records of the Auckland Institute and Museum - Auckland Institute; Museum. (Auckland Institute and Museum, 1982)

Records of the Auckland Institute and Museum - Auckland Institute; Museum. (Auckland Institute and Museum, 1983)

Records of the Auckland Institute and Museum - Auckland Institute; Museum. (Auckland Institute and Museum, 1984)

Records of the Auckland Institute and Museum - Auckland Institute; Museum. (Auckland Institute and Museum, 1987)

Records of the Auckland Institute and Museum - Auckland Institute; Museum. (Auckland Institute and Museum, 1994)

Records of the Australian Museum - Australian Museum (Printed by order of the Trustees, 2013)

Records of the Botanical Survey of India - Botanical Survey of India. (Office of Supt. of Govt. Print., India, 1893)

Records of the Botanical Survey of India - Botanical Survey of India. (Office of Supt. of Govt. Print., India, 1902)

Records of the Botanical Survey of India - Botanical Survey of India. (Office of Supt. of Govt. Print., India, 1921)

Records of the Queen Victoria Museum Launceston - Queen Victoria Museum (Launceston, Tas.) (The Museum, 1966)

Records of the Western Australian Museum - Western Australian Museum (Western Australian Museum, 2019)

Recueil des travaux botaniques néerlandais - Koninklijke Nederlandse Botanische Vereniging. (Société botanique néerlandaise, 1904)

Recueil des travaux botaniques néerlandais - Koninklijke Nederlandse Botanische Vereniging. (Société botanique néerlandaise, 1922)

Red list of the endemic plants of the Caucasus : Armenia, Azerbaijan, Georgia, Iran, Russia, and Turkey - Missouri Botanical Garden. (Missouri Botanical Garden Press, 2014)

Regiones terrestres prioritarias de México - Aguilar Zúñiga, Claudia (Comisión Nacional para el Conocimiento y Uso de la Biodiversidad (CONABIO), 2000)

Reise durch Nord-Amerika bis zur Mündung des grossen Fischflusses und an des Küsten des Polarmeeres in den Jahren 1833, 1834 und 1835 - Back, George, 1796 -1878 (J.J. Weber, 1836)

Reise in das innere Nord-America in den Jahren 1832 bis 1834 - Wied, Maximilian, Prinz von, 1782 -1867 (Bei J. Hœlscher, 1841)

Reise in den äussersten Norden und Osten Sibiriens während der Jahre 1843 und 1844 mit Allerhöchster Genehmigung auf Veranstaltung der Kaiserlichen Akademie der Wissenschaften zu St. Petersburg ausgeführt und in Verbindung mit vielen Gelehrten - Imperatorskai︠a︡ akademīi︠a︡ nauk (Russia) (Buchdr. der K. Akademie der Wissenschaften : Zu haben bei Eggers, 1856)

Reise in Ostafrika in den Jahren 1903-1905 : mit Mitteln der Hermann und Elise geb. Heckmann Wentzel-Stiftung : Wissenschaftliche Ergebnisse - Voeltzkow, Alfred, 1860 -1946 (E. Schweizerbartsche Verlagsbuchhandlung, 1917)

Reisen in Amur-Land und auf der Insel Sachalin : im Auftrage der Kaiserlich-Russischen Geographischen Gesellschaft ausgefuehrt - Schmidt, Friedrich, 1832 -1908 (Commissionaires de l'Académie impériale des sciences, 1868)

Reisen in Britisch-Guiana in den Jahren 1840-1844 : nebst einer Fauna und Flora Guiana's nach Vorlagen von Johannes Müller, Ehrenberg, Erichson, Klotzsch, Troschel, Cabanis und Andern - Ehrenberg, Christian Gottfried, 1795 -1876 (J. J. Weber, 1847)

Reistochten naar de Geelvinkbaai op Nieuw-Guinea in de jaren 1869 en 1870 - Koninklijk Instituut voor Taal-, Land- en Volkenkunde (Netherlands) (Nijhoff, 1875)

Reliquiae Formánekianae : enumeratio critica plantarum vascularium, quas itineribus in Haemo Peninsula et Asia Minore (Bithynia) factis collegit Dr. Ed. Formánek - Vandas, Karel, 1861 -1923 (Comitiorum Marchionatus Moraviae, 1909)

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)

Repertorium annuum literaturae botanicae periodicae - Bemmelen, J. A. van. (Erven Loosjes, 1873)

Repertorium botanices systematicae - Walpers, Wilhelm Gerhard, 1816 -1853 (Sumtibus Friderici Hofmeister, 1843)