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

Opinions and declarations rendered by the International Commission on Zoological Nomenclature - International Commission on Zoological Nomenclature (Printed by order of the International Trust for Zoological Nomenclature, 1958)

Opinions and declarations rendered by the International Commission on Zoological Nomenclature - International Commission on Zoological Nomenclature (Printed by order of the International Trust for Zoological Nomenclature, 1956)

Opinions and declarations rendered by the International Commission on Zoological Nomenclature - International Commission on Zoological Nomenclature (Printed by order of the International Trust for Zoological Nomenclature, 1957)

Opinions and declarations rendered by the International Commission on Zoological Nomenclature - International Commission on Zoological Nomenclature (Printed by order of the International Trust for Zoological Nomenclature, 1955)

Opinions and declarations rendered by the International Commission on Zoological Nomenclature - International Commission on Zoological Nomenclature (Printed by order of the International Trust for Zoological Nomenclature, 1959)

Optical activity and living matter - Gauze, G. F. (Georgiĭ Frant︠s︡evich) 1910 -1986 (Biodynamica, 1941)

Opuscula subseciva, observationes miscellaneas de animalculis et plantis quibusdam marinis, eorumque ovariis et seminibus continentia - Baster, Job, 1711 -1775 (apud J. Bosch, 1762)

The Orkney book : readings for young Orcadians - Gunn, John. (T. Nelson, 1909)

Ornis - International Ornithological Committee. (Carl Gerold's Sohn, 1886)

Ornis - International Ornithological Committee. (Carl Gerold's Sohn, 1889)

Ornithological notes - Herrick, C. L. (Clarence Luther), 1858 -1904 (Geological and Natural History Survey of Minnesota, 1877)

Ornithologie du Pérou - Taczanowski, Władysław, 1819 -1890 (Typographie Oberthur, 1886)

Ornithologie Nordost-Afrika's : der Nilquellen- und Küsten Gebiete des Rothen Meeres und des nördlichen Somal-Landes - Heuglin, Theodor von, 1824 -1876 (T. Fischer, 1869)

Der Ornithologische Beobachter - Ala, Schweizerische Gesellschaft für Vogelkunde und Vogelschutz. (Ala, Schweizerische Gesellschaft für Vogelkunde und Vogelschutz, 1916)

Ornithologische Monatsberichte (Verlag von R. Friedländer & Sohn, 1900)

Ornithologische Monatsberichte (Verlag von R. Friedländer & Sohn, 1916)

Ornithologische Monatsschrift - Deutscher Verein zum Schutze der Vogelwelt. (Kommissions-Verlag der Creutschen Verlagsbuchhandlung, 1905)

Die österreichische Polarstation Jan Mayen, ausgerüstet durch Graf Hanns Wilczek, geleitet vom Emil Edlen von Wohlgemuth. Beobachtungs-Ergebnisse, hrsg. von der Kaiserlichen Akademie der Wissenschaften - International Polar Expedition 1882 -1883 (In Commission bei K. Gerold's Sohn, 1886)

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

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

Our floating population : buoy collecting 1937-1940 - Gray, George M. (1940)

Our living resources : a report to the nation on the distribution, abundance, and health of U.S. plants, animals, and ecosystems - United States. National Biological Service. (U.S. Dept. of the Interior, National Biological Service, 1995)

Our living world; an artistic edition of the Rev. J. G. Wood's Natural history of animate creation - Wood, J. G. (John George), 1827 -1889 (S. Hess, 1885)

Outlines of comparative anatomy and medical zoology - Allen, Harrison, 1841 -1897 (Lippincott, 1874)

Outlines of comparative anatomy and medical zoology - Allen, Harrison, 1841 -1897 (J.B. Lippincott & co, 1869)

Outlines of physiology: with an appendix on phrenology - Roget, Peter Mark, 1779 -1869 (Lea and Blanchard, 1839)

Outlines of the natural history of Great Britain and Ireland, containing a systematic arrangement and concise description of all the animals, vegetables and fossiles which have hitherto been discovered in these kingdoms - Berkenhout, John, 1730 -1791 (Printed for P. Elmsly (Successor to Mr. Vaillant), 1769)

Outlines of zoology - Thomson, J. Arthur (John Arthur), 1861 -1933 (Young J. Pentland, 1892)

Outlines of zoology - Thomson, J. Arthur (John Arthur), 1861 -1933 (D. Appleton & Co, 1892)

Outlines of zoology - Thomson, J. Arthur (John Arthur), 1861 -1933 (Young J. Pentland, 1895)

Outlines of zoology - Thomson, J. Arthur (John Arthur), 1861 -1933 (Pentland, 1899)

Outlines of zoology - Thomson, J. Arthur (John Arthur), 1861 -1933 (D. Appleton & Co, 1895)

Outlines of zoology - Thomson, J. Arthur (John Arthur), 1861 -1933 (H. Frowde and Hodder & Stoughton, 1899)

Outlines of zoology - Thomson, J. Arthur (John Arthur), 1861 -1933 (Appleton, 1916)

Outlines of zoology - Thomson, J. Arthur (John Arthur), 1861 -1933 (D. Appleton, 1906)

Outlines of zoology - Thomson, J. Arthur (John Arthur), 1861 -1933 (Humphrey Milford, Oxford University Press, 1929)

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, 1842)

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, 1846)

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, 1901)

Oversigt over det vestilge Grønlands fauna af malakostrake Havkrebsdyr - Hansen, H. J. (Hans Jacob), 1855 -1936 ([Bianco Luno], 1887)

Ovum - Thomson, Allen, 1809 -1884 ([s.n.], 1856)

P.A. Latreille scientiarum et artium instituti Gallici ... Genera crustaceorum et insectorum : secundum ordinem naturalem in familias disposita, iconibus exemplisque plurimis explicata - Latreille, P. A. (Pierre André), 1762 -1833 (Apud Amand Knig, Bibliopolam, 1806)

Pacific science - University of Hawaii. (University Press of Hawaii, 1959)

Palaeontology - Palaeontological Association (Palaeontological Association, 1965)

Palæontology, invertebrate - Woods, Henry, 1868 -1952 (The University press, 1909)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1881)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1888)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1895)

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Papers in marine biology and oceanography (Pergamon Press, 1955)

Parasites : a treatise on the entozoa of man and animals, including some account of the ectozoa - Cobbold, T. Spencer (Thomas Spencer), 1828 -1886 (J. & A. Churchill, 1879)

Parasites a treatise on the entozoa of man and animals including some account of the ectozoa - Cobbold, T. Spencer (Thomas Spencer), 1828 -1886 (J. & A. Churchill, 1879)

The parasites of man, and the diseases which proceed from them; a textbook for students and practitioners - Leuckart, Rudolf, 1823 -1898 (Pentland, 1886)

The parasites of man, and the diseases which proceed from them : a text-book for students and practitioners - Leuckart, Rudolf, 1823 -1898 (Young J. Pentland, 1886)

The parasites of man, and the diseases which proceed from them. A text-book for students and practitioners - Leuckart, Rudolf, 1823 -1898 (Y.J. Pentland, 1886)

Parasites : a treatise on the entozoa of man and animals including some account of the ectozoa - Cobbold, T. Spencer (Thomas Spencer), 1828 -1886 (J. & A. Churchill, 1879)

Le parasitisme et la symbiose - Caullery, Maurice, 1868 -1958 (Doin, 1922)

Parasitology - British Society for Parasitology. (Cambridge University Press, 1908)

Parasitology - British Society for Parasitology. (Cambridge University Press, 1917)

Parasitology (Cambridge University Press, 1920)

Parasitology (Cambridge University Press, 1921)

Parks : a manual of municipal and county parks compiled as a result of a nation-wide study of municipal and county parks conducted by the Playground and Recreation Association of America, in co-operation with the American Institute of Park Executives at the request of the National Conference on Outdoor Recreation - American Institute of Park Executives. (A.S. Barnes & Co, 1928)

Periculum entomologicum - Thunberg, Carl Peter, 1743 -1828 (Litteris director. Joh. Edman, 1789)

The Permo-Carboniferous red beds of North America and their vertebrate fauna - Case, E. C. (Ermine Cowles), 1871 -1953 (Carnegie institution of Washington, 1915)

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Pesticides monitoring journal - United States. Chemical Information Division. (Technical Services Division, Office of Pesticide Programs, U.S. Environmental Protection Agency, 1967)

Die Petrefactenkunde auf ihrem jetzigen Standpunkte durch die Beschreibung seiner Sammlung versteinerter und fossiler Überreste des Thier-und pflanzenreichs der Vorwelt erläutert - Schlotheim, E. F. Freiherr von, (Ernst Friedrich), 1764 -1832 (1820)

Petri Bellonii Cenomani De aquatilibus, libri duo cum [epsilon, iota] conibus ad viuam ipsorum effigiem, quoad eius fieri potuit, expressis - Belon, Pierre, 1517? -1564 (Apud C. Stephanum, 1553)

Petri Matthioli ... Opera quae extant òmnia, hoc est, Commentarii in VI. libros Pedacii Dioscoridis Anazarbei De medica materia : adjectis in margine variis Graeci testus lectionibus, ex antiquissimis codicibus desumptis, qui Dioscorides depravatam lectionem restituunt - Bauhin, Caspar, 1560 -1624 (Sumptibus Joannis König, 1674)

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

Pflügers Archiv für die gesamte Physiologie des Menschen und der Tiere (M. Hager, 1910)

Pflügers Archiv für die gesamte Physiologie des Menschen und der Tiere (M. Hager, 1915)

Pflügers Archiv für die gesamte Physiologie des Menschen und der Tiere (M. Hager, 1918)

Pflügers Archiv für die gesamte Physiologie des Menschen und der Tiere (M. Hager, 1920)

Pflügers Archiv für die gesamte Physiologie des Menschen und der Tiere (M. Hager, 1911)

Philosophical transactions of the Royal Society of London - Royal Society (Great Britain) (Royal Society of London, 1835)

Philosophical transactions of the Royal Society of London - Royal Society (Great Britain) (Royal Society of London, 1840)

Philosophical transactions of the Royal Society of London - Royal Society (Great Britain) (Royal Society of London, 1879)

The philosophy of zoology, or, A general view of the structure, functions, and classification of animals - Fleming, John, 1785 -1857 (Hurst, Robinson & Co, 1822)

The philosophy of zoology; or, A general view of the structure, functions, and classification of animals - Fleming, John, 1785 -1857 (A. Constable, 1822)