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Opuscules de botanique - Clos, Dominique, 1821 -1908 (1859)

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The Osprey (The Osprey Co, 1899)

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

The Ottawa naturalist - Ottawa Field-Naturalists' Club (Ottawa Field-Naturalists' Club, 1903)

The Ottawa naturalist - Ottawa Field-Naturalists' Club (Ottawa Field-Naturalists' Club, 1912)

The Ottawa naturalist - Ottawa Field-Naturalists' Club (Ottawa Field-Naturalists' Club, 1913)

The Ottawa naturalist - Ottawa Field-Naturalists' Club (Ottawa Field-Naturalists' Club, 1914)

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)

Outlines of evolutionary biology - Dendy, Arthur, 1865 -1925 (D. Appleton and company, 1912)

Outlines of evolutionary biology - Dendy, Arthur, 1865 -1925 (Constable, 1912)

Outlines of evolutionary biology - Dendy, Arthur, 1865 -1925 (D. Appleton and company, 1914)

Over de bevruchting der bloemen in het kempisch gedeelte van Vlaanderen - MacLeod, Julius, 1857 -1919 (Vuylsteke, 1894)

Pacific Northwest ecoclass codes for plant associations - Hall, Frederick C. (USDA, Forest Service, Pacific Northwest Region, 1988)

Palestine : the physical geography and natural history of the Holy Land - Kitto, John, 1804 -1854 (Charles Knight, 1841)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1885)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1888)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1890)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1895)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1896)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1904)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1914)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1918)

Paxton's Botanical dictionary; comprising the names, history, and culture of all plants known in Britain; with a full explanation of technical terms. New ed. including all the new plants up to the present year - Paxton, Joseph, Sir, 1803 -1865 (Bradbury, Evans, & co, 1868)

Pehr Kalms Resa till Norra Amerika - Kalm, Pehr, 1716 -1779 (Tidnings & tryckeri-aktiebolagets tryckeri, 1904)

Pestmegye és tájéka viránya - Gönczy, Pál, 1817 -1892 (Ráth mór Bizománya, 1864)

Peter D. Knieskern and John Torrey correspondence, 1836-1858 - Knieskern, Peter D., 1798 -1871 (1844)

Peter D. Knieskern and John Torrey correspondence, 1836-1858 - Knieskern, Peter D., 1798 -1871 (1845)

Peter D. Knieskern and John Torrey correspondence, 1836-1858 - Knieskern, Peter D., 1798 -1871 (1847)

Petite flore de Belgique à l'usage des écoles - Cogniaux, Alfred, 1841 -1916 (Hector Manceaux, 1883)

Petite flore de la Mayenne - Léveillé, H. (Hector), 1863 -1918 (Goupil, 1895)

P.F. Cürie's Anleitung, die im mittleren und nördlichen Deutschland wildwachsenden und angebauten Pflanzen auf eine leichte und sichere Weise durch eigene Untersuchung zu bestimmen - Cürie, P. F. (C.G. Zobel, 1856)

Pflanzen-geographie auf physiologischer Grundlage - Schimper, A. F. W. (Andreas Franz Wilhelm), 1856 -1901 (Gustav Fischer, 1908)

Pflanzen-teratologie systematisch geordnet - Penzig, O. (Ottone), 1856 -1929 (A. Ciminago, 1894)

Die Pflanzen und Raupen Deutschlands : Versuch einer lepidopterologischen Botanik - Wilde, O. (E.S. Mittler, 1860)

Die Pflanzendecke der Erde : populäre Darstellung der Pflanzengeographie für gebildete Naturfreunde - Rudolph, Ludwig, 1813 -1896 (Nicolaische Verlagsbuchhandlung, 1859)

Die Pflanzendecke Österreich-Ungarns. Auf Grund fremder und eigener Forschungen geschildert - Hayek, August von, 1871 -1928 (F. Deuticke, 1914)

Die Pflanzenfeinde aus der Klasse der Insekten. Ein nach Pflanzenfamilien geordnetes Handbuch sämmtlicher auf den einheimischen Pflanzen bisher beobachteten Insekten zum Gebrauch für Entomologen, Insektensammler, Botaniker, Land- und Forstwirthe und Gartenfreunde - Kaltenbach, J. H. (Johann Heinrich), 1807 -1876 (J. Hoffmann, 1874)

Pflanzenphysiologie als Theorie der Gärtnerei. Für Botaniker, Gärtner, Landwirte, Forstleute und Pflanzenfreunde - Molisch, Hans, 1856 -1937 (G. Fischer, 1922)

Pflanzenphysiologie; ein Handbuch der Lehre vom Stoffwechsels und Kraftwechsels in der Pflanze - Pfeffer, W. (Wilhelm), 1845 -1920 (W. Engelmann, 1897)

Pflanzenphysiologie; ein Handbuch der Lehre vom Stoffwechsel und Kraftwechsel in der Pflanze - Pfeffer, W. (Wilhelm), 1845 -1920 (W. Engelmann, 1897)

Pflanzenphysiologie. Ein Handbuch des Stoffwechsels und Kraftwechsels in der Pflanze - Pfeffer, W. (Wilhelm), 1845 -1920 (W. Engelmann, 1881)

Pflanzenphysiologie. Ein handbuch des stoffwechsels und kraftwechsels in der pflanze - Pfeffer, W. (Wilhelm), 1845 -1920 (W. Engelmann, 1881)

Die Pflanzenwelt Dalmatiens - Adamović, Lujo (Lujo V.), 1869 -1935 (W. Klinkhardt, 1911)

The phantom of organic evolution - Price, George McCready, 1870 -1963 (Fleming H. Revell Company, 1924)

Pharmaceutical journal and transactions - Pharmaceutical Society of Great Britain (J. & A. Churchill, 1872)

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The Philosophical magazine and journal : comprehending various branches of science, the liberal and fine arts, agriculture, manufactures, and commerce (R. Taylor, 1819)

Physiographiska Sällskapets Årsberättelse - Physiographiska Sallskapet i Lund. (1823)

Physiographiska Sällskapets Tidskrift - Physiographiska Sallskapet i Lund (1837)

The physiology of plants; a treatise upon the metabolism and sources of energy in plants - Pfeffer, W. (Wilhelm), 1845 -1920 (Clarendon press, 1900)

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Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1981)

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The Phytologist: a botanical journal - Irvine, Alexander, 1793 -1873 (William Pamplin, 1855)

The Phytologist: a botanical journal - Irvine, Alexander, 1793 -1873 (William Pamplin, 1857)

The Phytologist: a botanical journal - Irvine, Alexander, 1793 -1873 (William Pamplin, 1858)

The Phytologist: a botanical journal - Irvine, Alexander, 1793 -1873 (William Pamplin, 1860)

The Phytologist: a botanical journal - Irvine, Alexander, 1793 -1873 (William Pamplin, 1861)

The Phytologist: a botanical journal - Irvine, Alexander, 1793 -1873 (William Pamplin, 1862)

The Phytologist: a popular botanical miscellany - Newman, Edward, 1801 -1876 (John van Voorst, 1841)

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The Phytologist: a popular botanical miscellany - Newman, Edward, 1801 -1876 (John van Voorst, 1850)

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Phytoneuron (Guy L. Nesom, 2011)

Phytoneuron (Guy L. Nesom, 2013)

Phytoneuron (Guy L. Nesom, 2014)

Phytoneuron (Guy L. Nesom, 2015)

Phytoneuron (Guy L. Nesom, 2018)

Le piante fanerogame della Svissera insubrica : enumerate seconde il metodo decandolliano - Favrat, Louis, 1827 -1893 (H. Georg, 1890)

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Pittonia :a series of papers relating to botany and botanists - Greene, Edward Lee, 1843 -1915 (Doxey & Co. [etc.], 1899)

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Plant-geography upon a physiological basis - Balfour, Isaac Bayley, 1853 -1922 (Clarendon Press, 1903)

Plant-life - Hall, Charles A. (Charles Albert), 1872 -1965 (A. & C. Black, 1915)

Plant-life - Hall, Charles A. (Charles Albert), 1872 -1965 (Black, 1915)

Plant life in Alpine Switzerland; being an account in simple language of the natural history of Alpine plants - Arber, E. A. Newell (Edward Alexander Newell), 1870 -1918 (J. Murray, 1910)

The plant life of Hartsville, S.C - Coker, William Chambers, 1872 -1953 ([Pee Dee Historical Assn.], 1912)

The plant life of Maryland - Shreve, Forrest, 1878 -1950 (Johns Hopkins Press, 1910)

Plant lists and correspondence - Barkley, Fred A. (Fred Alexander), 1908 -1989 (1949)

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Plantæ favershamienses : a catalogue of the more perfect plants growing spontaneously about Faversham, in the county of Kent - Jacob, Edward, 1709 or 1710 -1788 (Printed for the author; by J. March, 1777)

Plantæ Woodfordienses : a catalogue of the more perfect plants growing spontaneously about Woodford, in the county of Essex - Warner, Richard, 1713? -1775 (Printed for the author, 1771)

Plantas Romaniae hucusque cognitas - Kanitz, Ágost, 1843 -1896 (Apud E. Demjén, 1879)

Les plantes industrielles - Heuzé, Gustave, 1816 -1907 (L. Hachette, 1859)

Plantes vasculaires des environs de Cherbourg - Le Jolis, Auguste, 1823 -1904 (J.B. Baillière, 1860)

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