Plantas de la Amazonía peruana : clave para identificar las familias de Gymnospermae y Angiospermae - Vásquez Martínez, Rodolfo (Museo de Historia Natural, 2004)

De planten in den botanischen tuin bij het Groot militair hospitaal te Weltevreden - Filet, G. J., 1825 -1891 (Lange, 1855)

Plantenkunde voor Indië - Haak, J. (G. C. T. Van Dorp & Co, 1892)

Les plantes vasculaires rares du Canada : notre patrimoine naturel - Argus, George W. (George William) (Programme des plantes rares et menacées, Musée canadien de la nature, 1990)

Plants in Danger: what do we know? (1986)

Plants of possible insecticidal value : a review of the literature up to 1941 - United States. Office of Experiment Stations. (U.S. Dept. of Agriculture, Agricultural Research Administration, Bureau of Entomology and Plant Quarantine, 1945)

Plants of the U.S. Military Academy, West Point, New York - Barringer, Kerry Alan (Brooklyn Botanic Garden, 1990)

Poisonous and Injurious Plants of the U. S. Virgin Islands - Butcher, James O. (James Owsley), 1932 - (1962)

Pollen and spores of Barro Colorado Island - Roubik, David W. (David Ward), 1951 - (Missouri Botanical Garden, 1991)

The Popular educator: a complete encyclopaedia of elementary, advanced and technical education (Cassell, 1888)

Populäre Botanik oder gemeinfassliche Anleitung zum Studium der Pflanze und des Pflanzenreiches. Zugleich ein Handbuch zum Bestimmen der Pflanzen auf Excursionen - Schmidlin, Eduard, 1808? -1890 (Krais & Hoffmann, 1857)

Pre-project study on the conservation status of tropical timbers in trade. Final report to International Tropical Timber Organization. Vol 1 - Oldfield, Sara (ITTO, 1991)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1841)

Proceedings of the California Academy of Sciences, 4th series - California Academy of Sciences (California Academy of Sciences, 1988)

Proceedings of the California Academy of Sciences, 4th series - California Academy of Sciences (California Academy of Sciences, 1989)

Proceedings of the California Academy of Sciences, 4th series - California Academy of Sciences (California Academy of Sciences, 2006)

Proceedings of the Entomological Society of Washington - Entomological Society of Washington (Entomological Society of Washington, 1975)

Proceedings of the Entomological Society of Washington - Entomological Society of Washington (Entomological Society of Washington, 1985)

Proceedings of the Entomological Society of Washington - Entomological Society of Washington (Entomological Society of Washington, 1998)

Proceedings of the Entomological Society of Washington - Entomological Society of Washington (Entomological Society of Washington, 2002)

Proceedings of the Entomological Society of Washington - Entomological Society of Washington (Entomological Society of Washington, 2004)

Proceedings of the Florida Academy of Sciences - Florida Academy of Sciences. (Rose Printing Co., etc, 1936)

Proceedings of the Linnean Society of New South Wales - Linnean Society of New South Wales. (Linnean Society of New South Wales, 1977)

Proceedings of the Nova Scotian Institute of Science - Nova Scotian Institute of Science. (Nova Scotian Institute of Science, 2010)

The Proceedings of the Royal Society of Queensland - Royal Society of Queensland. (Royal Society of Queensland], 2011)

Proceedings of the Royal Society of Victoria. New series - Royal Society of Victoria (Melbourne, Vic.) (Stillwell and Co, 1990)

Proceedings of the Royal Society of Victoria. New series - Royal Society of Victoria (Melbourne, Vic.) (Stillwell and Co, 2000)

Proceedings : Sagebrush Steppe Ecosystems Symposium : Boise State University, Boise, Idaho, June 21-23, 1999 - DeBolt, Ann (U.S. Department of the Interior, Bureau of Land Management, Idaho State Office, 1999)

Prodromus florae Novo-Granatensis - Planchon, Jules-Emile, 1823 -1888 (V. Masson, 1862)

A provisional checklist of species for Flora North America - Shetler, Stanwyn G. (Published for MAB/FNA by Missouri Botanical Garden, 1978)

Psyche - Cambridge Entomological Club. (Cambridge Entomological Club, 2012)

Publication. Field Museum of Natural History Botanical series - Field Museum of Natural History. (Field Museum of Natural History, 1930)

Publication. Field Museum of Natural History Botanical series - Field Museum of Natural History. (Field Museum of Natural History, 1929)

Publications in botany - National Museum of Natural Sciences (Canada) (The Museum, 1981)

Quarterly journal of the Florida Academy of Sciences - Florida Academy of Sciences. (Florida Academy of Sciences, 1952)

Rapid biological inventories - Field Museum of Natural History. Environmental; Conservation Programs. (Field Museum, 2000)

Rapid biological inventories - Field Museum of Natural History. Environmental; Conservation Programs. (Field Museum, 2001)

Rapid biological inventories - Field Museum of Natural History. Environmental; Conservation Programs. (Field Museum, 2002)

Rapid biological inventories - Field Museum of Natural History. Environmental; Conservation Programs. (Field Museum, 2003)

Rapid biological inventories - Field Museum of Natural History. Environmental; Conservation Programs. (Field Museum, 2005)

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, 2004)

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 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)

Reading Naturalist. Reading - Reading Natural History Society.

Records of the Queen Victoria Museum Launceston - Queen Victoria Museum (Launceston, Tas.) (The Museum, 1996)

Records of the Queen Victoria Museum Launceston - Queen Victoria Museum (Launceston, Tas.) (The Museum, 2003)

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

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, 1848)

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)

Releases of beneficial organisms in the United States and territories, 1982 - United States. Agricultural Research Service. (U.S. Dept. of Agriculture, Agricultural Research Service, 1992)

Releases of beneficial organisms in the United States and territories, 1983 - United States. Agricultural Research Service. (U.S. Dept. of Agriculture, Agricultural Research Service, 1994)

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)