Oesterreichisches botanisches Wochenblatt ([L.W. Seidel], 1854)

Öfversigt af Kongl. Vetenskaps-akademiens forhandlingar - Kungl. Svenska vetenskapsakademien. (P. A. Norstedt & Söner, 1861)

Öfversigt af Kongl. Vetenskaps-akademiens forhandlingar - Kungl. Svenska vetenskapsakademien. (P. A. Norstedt & Söner, 1880)

Öfversigt af Kongl. Vetenskaps-akademiens forhandlingar - Kungl. Svenska vetenskapsakademien. (P. A. Norstedt & Söner, 1883)

Öfversigt af Kongl. Vetenskaps-akademiens forhandlingar - Kungl. Svenska vetenskapsakademien. (P. A. Norstedt & Söner, 1884)

Öfversigt af Kongl. Vetenskaps-akademiens forhandlingar - Kungl. Svenska vetenskapsakademien. (P. A. Norstedt & Söner, 1887)

Öfversigt af Kongl. Vetenskaps-akademiens forhandlingar - Kungl. Svenska vetenskapsakademien. (P. A. Norstedt & Söner, 1894)

The Ohio naturalist - Ohio Academy of Science. (Biological Club of the Ohio State University, 1906)

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

L'Oiseau et la Revue francaise d'ornithologie - Société ornithologique de France. (Société ornithologique de France, 1983)

Om Salixvegetationen i Klarelfvens floddal ... - Skårman, Johan Albert Otto, 1862 - (Almqvist & Wiksell boktryckeri-aktiebolag, 1892)

Om Westeråstrakten i botaniskt afseende - Troilius, Adolf Magnus, 1838 -1909 (Tryckt hos E. Westrell, 1860)

Opera e periodicis collata - Vries, Hugo de, 1848 -1935 (A. Oosthoek, 1918)

The orchids in the Ottawa District : floristics, phytogeography, population studies and historical review / Joyce M. Reddoch and Allan H. Reddoch - Ottawa Field-Naturalists' Club (The Ottawa Field-Naturalists' Club, 1997)

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 the British flora - Reid, Clement, 1853 -1916 (Dulau, 1899)

L'origine et le développement des flores dans le massif central de France; avec aperçu sur les migrations des flores dans l'Europe sud-occidentale - Braun-Blanquet, J. (Josias), 1884 -1980 (L. Lhomme, 1923)

Die Ostsudeten; eine floristische Skizze - Hruby, Johann. (Landesdurch-forschungs-Komemission, 1914)

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

Oversigt over det Kongelige Danske videnskabernes selskabs forhandlinger = Bulletin de l'Académie royale des sciences et des lettres de Danemark - Kongelige Danske videnskabernes selskab. (A.F. Høst, 1869)

Une page d'histoire de la medecine : la thérapeutique sous les premiers Césars - Lépine, R. (Raphael), 1840 -1919 (F. Alcan, 1890)

Die palaeobotanische Literatur : bibliographische Übersicht über die Arbeiten aus dem Gebiete der Palaeobotanik - Jongmans, W. (Willem), 1878 -1957 (Fischer, 1911)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1885)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1887)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1888)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1891)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1895)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1896)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1900)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1916)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1917)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1918)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 2000)

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

Das Pflanzenleben der Schweiz - Christ, H. (Hermann), 1833 -1933 (F. Schulhess, 1882)

Die Pflanzenstoffe, botanisch-systematisch bearbeitet ; chemische Bestandteile und Zusammensetzung der einzelnen Pflanzenarten, Rohstoffe und Produkte. Phanerogamen - Wehmer, C. (Carl), 1858 -1935 (G. Fischer, 1911)

Die Pflanzenwelt Deutschlands; Lehrbuch der Formations- biologie. Eine Darstellung der Lebensgeschichte der wildwachsenden Pflanzenvereine und der Kulturflächen - Graebner, Paul, 1871 -1933 (Quelle & Meyer, 1909)

Die Pflanzenwelt Norwegens : ein Beitrag zur Natur- und Culturgeschichte Nord-Europas - Schübeler, F. C. (Frederik Christian), 1815 -1892 (1873)

Die Phanerogamen - Flora Oesels und der benachbarten Eilande und Beitrag zur Flora der Insel Runoe - Sass, Arthur, Baron von. (Druck von H. Laakmann, 1860)

Pharmaceutical journal and transactions - Pharmaceutical Society of Great Britain. (J. & A. Churchill, 1877)

Pharmaceutical journal and transactions - Pharmaceutical Society of Great Britain. (J. & A. Churchill, 1875)

Pharmaceutical journal and transactions - Pharmaceutical Society of Great Britain. (J. & A. Churchill, 1879)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1968)

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, 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)

The Phytologist: a popular botanical miscellany - Newman, Edward, 1801 -1876 (John van Voorst, 1847)

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

Phytoneuron (Guy L. Nesom, 2014)

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

Le piante fanerogame della Svizzera insubrica : enumerate secondo il methodo decandolliano - Favrat, Louis, 1827 -1893 (H. Georg, 1890)

Die Pilze Böhmens - Bubák, František, 1866 -1925 (In Commission bei F. ivna, 1908)

The Plant world - Plant World Association. (Plant World Association [etc.], 1910)

Plantevæxten paa Færøerne : med sæerlig hensyntagen til blomsterplanterne - Ostenfeld, C. H. (Carl Hansen), 1873 -1931 (Gyldendal, 1906)

Plants of Iowa; a preliminary list of the native and introduced plants of the state, not under cultivation - Greene, Wesley. (Bishard brothers, printers, 1907)

The plants of Michigan; simple keys for the identification of the native seed plants of the state - Gleason, Henry A. (Henry Allan), 1882 -1975 (G. Wahr, 1918)

The plants of Prince Edward Island - Erskine, D. S. (David Sterling) (Plant Research Institute, Research Branch, Canada Dept. of Agriculture, 1960)

The plants of Prince Edward Island - Erskine, D. S. (David Sterling) (Research Branch, Agriculture Canada, 1985)

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

Pollen - Edgeworth, Michael Pakenham, 1812 -1881 (Hardwicke & Bogue, 1877)

Popular field botany; containing a familiar and technical description of the plants most common to the various localities of the British Isles, adapted to the study of either the artificial or natural systems - Catlow, Agnes, 1807? -1889 (Reeve, Benham, and Reeve, 1848)

Popular field botany; containing a familiar and technical description of the plants most common to the various localities of the British Isles, adapted to the study of either the artificial or natural systems - Catlow, Agnes, 1807? -1889 (Reeve, Benham & Reeve, 1849)

Popular names of flowers, fruits, &c., as used in the county of Somerset and the adjacent parts of Devon, Dorset and Wilts - Macmillan, Alexander Stuart. (Western Gazette, 1922)

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)

Practical hints for the field lepidopterist I - Tutt, James William, 1858 -1911 (E. Stock, 1908)

Prehistoric Europe, a geological sketch - Geikie, James, 1839 -1915 (E. Stanford, 1881)

Prehistoric Europe : a geological sketch - Darwin, Charles, 1809 -1882 (Edward Stanford, 1881)

Preliminary catalog of Anthophyta and Pteridophyta, reported as growing spontaneously within one hundred miles of New York City - Torrey Botanical Club. (1888)

Preliminary catalogue of Anthophyta and Pteridophyta, reported as growing spontaneously within one hundred miles of New York City - Torrey Botanical Club. (1888)

A preliminary catalogue of the flora of Vancouver and Queen Charlotte Islands - British Columbia Provincial Museum. (Printed by W. H. Cullin, 1921)

Preliminary inventory of Canadian weeds - Crompton, Clifford W. (Agriculture Canada, Research Branch, 1988)

Prima lineae florae Herbipolensis - Lehmann, Johann Friedrich. (Nitribitt, 1809)

The primaeval world of Switzerland - Heer, Oswald, 1809 -1883 (Longmans, Green, 1876)

The principles of plant-teratology - Worsdell, Wilson Crosfield (The Ray Society, 1915)

La priorité des noms de plantes - Saint-Lager, Jean Baptiste, 1825 -1912 (Librarie J.-B. Baillière et fils, 1890)

Prirodoslovna istraživanja - Jugoslavenska akademija znanosti i umjetnosti. (1916)

Proceedings - Nova Scotian Institute of Science. (1866)

Proceedings - Dorset Natural History; Archaeological Society.

Proceedings (and Annual Report) of the Holmesdale Natural History Club, Reigate - Holmesdale Natural History Club. (1865)

Proceedings and transactions of the British Entomological and Natural History Society - British Entomological; Natural History Society. (British Entomological and Natural History Society, 1968)

Proceedings and transactions of the British Entomological and Natural History Society - British Entomological; Natural History Society. (British Entomological and Natural History Society, 1970)

Proceedings and transactions of the British Entomological and Natural History Society - British Entomological; Natural History Society. (British Entomological and Natural History Society, 1978)

Proceedings and Transactions of the Croydon Microscopical & Natural History Club - Croydon Microscopical; Natural History Club. (1889)

Proceedings and transactions of the South London Entomological & Natural History Society - South London Entomological; Natural History Society (The Society, 1953)

Proceedings and transactions of the South London Entomological & Natural History Society - South London Entomological; Natural History Society (The Society, 1962)

Proceedings and transactions of the South London Entomological & Natural History Society - South London Entomological; Natural History Society (The Society, 1965)

Proceedings - Cambridge Philosophical Society Mathematical and physical sciences - Cambridge Philosophical Society. (Cambridge Philosophical Society [etc.], 1910)

Proceedings - Dorset Natural History and Archaeological Society - Dorset Natural History; Archaeological Society. (1877)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1863)

Proceedings of the Boston Society of Natural History - Boston Society of Natural History. (Boston Society of Natural History, 1923)

Proceedings of the Botanical Society of the British Isles - Botanical Society of the British Isles. (1954)

Proceedings of the Botanical Society of the British Isles - Botanical Society of the British Isles. (1960)

Proceedings of the Botanical Society of the British Isles - Botanical Society of the British Isles. (1963)

Proceedings of the Botanical Society of the British Isles - Botanical Society of the British Isles. (1965)

Proceedings of the Botanical Society of the British Isles - Botanical Society of the British Isles. (1967)

Proceedings of the Bournemouth Natural Science Society - Bournemouth Natural Science Society (1923)

Proceedings of the Bournemouth Natural Science Society - Bournemouth Natural Science Society (1953)

Proceedings of the Bristol Naturalists' Society - Bristol Naturalists' Society (Bristol, England) (Bristol Naturalists' Society, 1866)

Proceedings of the Bristol Naturalists' Society - Bristol Naturalists' Society (Bristol, England) (Bristol Naturalists' Society, 1939)

Proceedings of the Bristol Naturalists' Society - Bristol Naturalists' Society (Bristol, England) (Bristol Naturalists' Society, 1944)

Proceedings of the Bristol Naturalists' Society - Bristol Naturalists' Society (Bristol, England) (Bristol Naturalists' Society, 1954)

Proceedings of the Bristol Naturalists' Society - Bristol Naturalists' Society (Bristol, England) (Bristol Naturalists' Society, 1959)

Proceedings of the Bristol Naturalists' Society - Bristol Naturalists' Society (Bristol, England) (Bristol Naturalists' Society, 1964)

Proceedings of the Bristol Naturalists' Society - Bristol Naturalists' Society (Bristol, England) (Bristol Naturalists' Society, 1981)

Proceedings of the Cotteswold Naturalists' Field Club - Cotteswold Naturalists' Field Club. (1901)

Proceedings of the Cotteswold Naturalists' Field Club - Cotteswold Naturalists' Field Club. (1910)

Proceedings of the Dublin University Zoological and Botanical Association - Dublin University. Zoological; Botanical Association.

Proceedings of the Literary and Philosophical Society of Liverpool - Literary; Philosophical Society of Liverpool. (1849)

Proceedings of the Natural History Society of Glasgow - Natural History Society of Glasgow. (Natural History Society of Glasgow, 1875)

Proceedings of the Nova Scotian Institute of Science - Nova Scotian Institute of Science. (Nova Scotian Institute of Science, 1969)

Proceedings of the Royal Irish Academy - Royal Irish Academy. (Royal Irish Academy, 1875)