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

Polypetalae disciflorae Rehmannianae : sive, Enumeratio Linearum, Malpighiacearum, Zygophyllearum ... a cl. Dr. A. Rehmann annis 1875-1880 in Africa australi extratropica collectarum - Szyszyłowicz, Ign. (Ignacy), 1857 -1910 (typis Universitatis Jagellonicae, 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)

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Preliminary report on the forest and other vegetation of Pegu - Kurz, Wilhelm Sulpiz, 1834 -1878 (Lewis, 1875)

Primae lineae systematis naturæ : nexui naturali omnium evolutionique progressivae per nixus reascendentes superstructi - Gori͡aninov, Pavel Fedorovich, 1796 -1865 (Typis Karoli Krajanis, 1834)

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Prodromus systematis naturalis regni vegetabilis, sive, Enumeratio contracta ordinum generum specierumque plantarum huc usque cognitarium, juxta methodi naturalis, normas digesta - Candolle, Augustin Pyramus de, 1778 -1841 (Sumptibus Sociorum Treuttel et Würtz, 1842)

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

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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)

Reliquiae Dewevreanae ou Enumération systématique des plantes récoltées par Alfr. Dewèvre en 1895-96 dans l'Etat Indépendant du Congo - De Wildeman, Emile 1866 -1947 (1901)

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)

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