Novon a journal of botanical nomenclature from the Missouri Botanical Garden - Missouri Botanical Garden. (Missouri Botanical Garden, 2017)

Nuova flora analitica d'Italia, contenente la descrizione delle piante vascolari indigene inselvatichite e largamente coltivate in Italia - Fiori, Adriano 1865 -1950 (Tipografia di M. Ricci, 1923)

The nursery-book : a complete guide to the multiplication and pollination of plants - Bailey, L. H. (Liberty Hyde), 1858 -1954 (The Rural Pub. Co, 1892)

The nursery-manual; a complete guide to the multiplication of plants - Bailey, L. H. (Liberty Hyde), 1858 -1954 (Macmillan, 1920)

De nuttige planten van Nederlandsch-Indië, tevens synthetische catalogus der verzamelingen van het Museum voor Technische- en Handelsbotanie te Buitenzorg - Heyne, K. (Ruygrok, 1913)

De nuttige planten van Nederlandsch-Indië tevens synthetische catalogus der verzamelingen van het Museum voor Economische Botanie te Buitenzorg - Heyne, K. (Ruygrok, 1922)

Nuytsia: journal of the Western Australian Herbarium - Western Australia. Department of Agriculture (Department of Biodiversity, Conservation and Attractions, 1999)

Nuytsia: journal of the Western Australian Herbarium - Western Australia. Department of Agriculture (Department of Biodiversity, Conservation and Attractions, 2015)

Nuytsia: journal of the Western Australian Herbarium - Western Australia. Department of Agriculture (Department of Biodiversity, Conservation and Attractions, 2016)

Nuytsia: journal of the Western Australian Herbarium - Western Australia. Department of Agriculture (Department of Biodiversity, Conservation and Attractions, 2022)

Nzayilu N'ti : Guide des arbres et arbustes de la région de Kinshasa - Brazzaville - Robbrecht, Elmar (1993)

Observations of a naturalist in the Pacific between 1896 and 1899 - Guppy, H. B. (Henry Brougham), 1854 -1926 (Macmillan and Co, 1903)

Observations of a naturalist in the Pacific between 1896 and 1899 - Guppy, H. B. (Henry Brougham), 1854 -1926 (Macmillan and co., limited, 1903)

Observations on the flowering plants, ferns and fern allies growing wild in Marquette County, Michigan, in 1916 and 1917, especially in the vicinity of the Huron Mountain Club - University of Michigan. Museum of Zoology. (Published by the University, 1918)

Occasional papers - San Diego Society of Natural History. (San Diego Society of Natural History, 1949)

Occasional papers of the California Academy of Sciences - California Academy of Sciences (California Academy of Sciences, 1993)

Occasional papers of the Farlow Herbarium of Cryptogamic Botany - Farlow Reference Library; Herbarium. (Harvard University, Farlow Herbarium of Cryptogamic Botany, 1981)

Occasional papers of the Museum of Natural History, the University of Kansas - University of Kansas. Museum of Natural History. (The University, 1989)

Occasional papers of the Museum of Natural History, the University of Kansas - University of Kansas. Museum of Natural History. (The University, 1990)

Oecology of plants : an introduction to the study of plant-communities - Vahl, M. (Martin), 1749 -1804 (Clarendon Press, 1909)

Oecology of plants : an introduction to the study of plant-communities - Warming, Eugenius, 1841 -1924 (Clarendon Press, 1909)

Oecology of plants; an introduction to the study of plant-communities - Balfour, Isaac Bayley, 1853 -1922 (Clarendon Press, 1909)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1877)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1880)

Oesterreichische botanische Zeitschrift (A. Skofitz)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1888)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1889)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1901)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1905)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1907)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1908)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1909)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1911)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1912)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1915)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1916)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1920)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1923)

Die officinellen Pflanzen der Pharmacopoea Germanica für Pharmaceuten und Mediciner besprochen und durch Originalabbildungen erläutert - Kohl, F. G. (Friedrich Georg), 1855 -1910 (Barth, 1895)

Die offizinellen Pflanzen und Drogen :eine systematische Übersicht über die in sämtlichen Staaten Europas sowie in Japan und den Vereinigten Staaten von Amerika offizinellen Pflanzen und Drogen mit kurzen erläuternden Bemerkungen - Mitlacher, Wilhelm, 1872 -1913 (C. Fromme, 1912)

Öfversigt af Finska vetenskaps-societetens förhandlingar - Suomen Tiedeseura (s.n.], 1905)

Ohio Biological Survey notes - Ohio Biological Survey. (Ohio Biological Survey, 2015)

Ohio Biological Survey notes - Ohio Biological Survey. (Ohio Biological Survey, 2017)

The Ohio journal of science - Ohio Academy of Science. (Ohio Academy of Science, 1909)

The Ohio naturalist - Ohio Academy of Science. (Biological Club of the Ohio State University, 1904)

The Ohio naturalist - Ohio Academy of Science. (Biological Club of the Ohio State University, 1903)

The Ohio naturalist - Ohio Academy of Science. (Biological Club of the Ohio State University, 1910)

The Ohio naturalist - Ohio Academy of Science. (Biological Club of the Ohio State University, 1911)

On Cephalozia (a genus of Hepaticae), its subgenera and some allied genera - Spruce, Richard, 1817 -1893 (Printed for the author, 1882)

On the taxonomic identity of Sturnira nana Gardner and O'Neil, 1971 (Chiroptera: Phyllostomidae), from Ecuador : with the description of a new species of Sturnira - Velazco, Paúl M. (American Museum of Natural History, 2023)

Onze flora. Beschrijving van de familiën, voornamste geslachten en soorten der in Nederland in het wild groeiende, verwilderde, verbouwde en aangeplante gewassen, alsmede van eenige fraaie en nuttige midden-europeesche planten - Hoffmann, Carl, 1802 -1883 (W.J. Thieme, 1900)

Orchidaceae: illustrations and studies of the family Orchidaceae - Ames, Oakes, 1874 -1950 (Houghton, Mifflin, 1920)

Orchidaceae: illustrations and studies of the family Orchidaceae - Ames, Oakes, 1874 -1950 (Houghton, Mifflin, 1922)

Oréades - Instituto de Ciências Biológicas da UFMG. Departamento de Botânica. (Departamento de Botânica, U.F.M.G, 1977)

Oréades - Instituto de Ciências Biológicas da UFMG. Departamento de Botânica. (Departamento de Botânica, U.F.M.G, 1981)

Oregon flora newsletter - Oregon State University. Department of Botany; Plant Pathology. (Oregon Flora Project, Dept. of Botany & Plant Pathology, Oregon State University, 2010)

Organic materia medica and therapeutics : in accordance with the sixth revision of the United States Pharmacopoeia - Simpson, James Young, Sir, 1811 -1870 (J.H. Vail, 1885)

Organographie der Pflanzen, insbesondere der Archegoniaten und Samenpflanzen - Goebel, K. (Karl), 1855 -1932 (G. Fischer, 1898)

Organography of plants, especially of the archegoniatae and spermaphyta - Goebel, K. (Karl), 1855 -1932 (Clar. Press, 1900)

The origin of a land flora : a theory based upon the facts of alternation - Bower, F. O. (Frederick Orpen), 1855 -1948 (Macmillan, 1908)

The origin of a land flora : a theory based upon the facts of alternation - Bower, F. O. (Frederick Orpen), 1855 -1948 (Macmillan and co., limited, 1908)

The origin of a land flora, a theory based upon the facts of alternation - Bower, F. O. (Frederick Orpen), 1855 -1948 (Macmillan and Co., Ltd, 1908)

Origin of cultivated plants - Candolle, Alphonse de, 1806 -1893 (K. Paul, Trench, 1884)

Origin of cultivated plants - Candolle, Alphonse de, 1806 -1893 (Paul, Trench, 1886)

Ornamental plant explorations, Japan, 1961 - United States. Agricultural Research Service. (Agricultural Research Service, U.S. Dept. of Agriculture in cooperation with Longwood Gardens of the Longwood Foundation, Inc, 1966)

The ornamental trees of Hawaii - Rock, Joseph F. (Joseph Francis), 1884 -1962 (1917)

Ornithological science - Nihon Chogakkai (Ornithological Society of Japan, 2002)

O.S.U. naturalist - Ohio State University. Biological Club. (Biological Club of Ohio State University, 1902)

Our early wild flowers a study of the herbaceous plants blooming in early spring in the northern states and Canada - Keeler, Harriet L. (Harriet Louise), 1846 -1921 (McClelland, Goodchild & Stewart, 1916)

Our early wild flowers : a study of the herbaceous plants blooming in early spring in the northern states - Keeler, Harriet L. (Harriet Louise), 1846 -1921 (Scribner, 1916)

Our South African flora = Ons Suid-Afrikaanse plantegroei - Compton, R. H. (Cape Times, 1900)

Out-of-the-ordinary bulbs for 1958 : 30 years of catering to the bulb collector - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Oakhurst Gardens, 1958)

Out-of-the-ordinary bulbs for 1958 : 31 years of catering to the bulb collector - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Oakhurst Gardens, 1959)

An outline of plant geography (The Macmillan company, 1926)