Primo resoconto dei risultati della inchiesta ornitologica in Italia ... - Giglioli, Enrico Hillyer, 1845 -1909 (Coi tipi dei successori Le Monnier, 1889)

Problems of evolution - Headley, F. W. (Frederick Webb), 1856 -1919 (Duckworth, 1900)

Proceedings and Transactions of the Croydon Microscopical & Natural History Club - Croydon Microscopical; Natural History Club. (1881)

Proceedings and transactions of the Natural History Society of Glasgow - Natural History Society of Glasgow. (The Society, 1883)

Proceedings and transactions of the Natural History Society of Glasgow - Natural History Society of Glasgow. (The Society, 1889)

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

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1883)

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Proceedings of the Boston Society of Natural History - Boston Society of Natural History. (Boston Society of Natural History, 1856)

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Proceedings of the Bournemouth Natural Science Society - Bournemouth Natural Science Society (1940)

Proceedings of the Bournemouth Natural Science Society - Bournemouth Natural Science Society (1947)

Proceedings of the Bristol Naturalists' Society - Bristol Naturalists' Society (Bristol, England) (Bristol Naturalists' Society, 1898)

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 California Academy of Sciences, 4th series - California Academy of Sciences (California Academy of Sciences, 1966)

Proceedings of the California Academy of Sciences, 4th series - California Academy of Sciences (California Academy of Sciences, 1965)

Proceedings of the Chester Society of Natural Science - Chester Society of Natural Science. (1874)

Proceedings of the International Ornithological Congress (Australian Academy of Science [etc.], 1891)

Proceedings of the International Ornithological Congress (Australian Academy of Science [etc.], 1911)

Proceedings of the International Ornithological Congress (Australian Academy of Science [etc.], 1951)

Proceedings of the International Ornithological Congress (Australian Academy of Science [etc.], 1955)

Proceedings of the International Ornithological Congress (Australian Academy of Science [etc.], 1960)

Proceedings of the International Ornithological Congress (Australian Academy of Science [etc.], 1962)

Proceedings of the International Ornithological Congress (Australian Academy of Science [etc.], 1980)

Proceedings of the International Ornithological Congress (Australian Academy of Science [etc.], 1982)

Proceedings of the International Ornithological Congress (Australian Academy of Science [etc.], 1990)

Proceedings of the International Ornithological Congress (Australian Academy of Science [etc.], 1991)

Proceedings of the Linnean Society of New South Wales - Linnean Society of New South Wales. (Linnean Society of New South Wales, 1922)

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Proceedings of the Natural History Society of Glasgow - Natural History Society of Glasgow. (Natural History Society of Glasgow, 1869)

Proceedings of the Natural History Society of Glasgow - Natural History Society of Glasgow. (Natural History Society of Glasgow, 1880)

Proceedings of the Royal Irish Academy - Royal Irish Academy. (Royal Irish Academy, 1911)

Proceedings of the Royal Physical Society of Edinburgh - Royal Physical Society of Edinburgh. (The Society, 1881)

Proceedings of the Royal Physical Society of Edinburgh - Royal Physical Society of Edinburgh. (The Society, 1885)

Proceedings of the Royal Physical Society of Edinburgh - Royal Physical Society of Edinburgh. (The Society, 1909)

Proceedings of the South London Entomological & Natural History Society - South London Entomological; Natural History Society (South London Entomological and Natural history Society, 1922)

Proceedings of the Symposium on Management of Forest and Range Habitats for Nongame Birds, May 6-9, 1975, Tucson, Arizona - United States. Forest Service. (U.S. Dept. of Agriculture, Forest Service, 1975)

Proceedings of the United States National Museum - Smithsonian Institution (Smithsonian Institution Press, [etc.], 1883)

Proceedings of the United States National Museum - Smithsonian Institution (Smithsonian Institution Press, [etc.], 1887)

Proceedings of the United States National Museum - Smithsonian Institution (Smithsonian Institution Press, [etc.], 1893)

Proceedings of the United States National Museum - Smithsonian Institution (Smithsonian Institution Press, [etc.], 1895)

Proceedings of the United States National Museum - Smithsonian Institution (Smithsonian Institution Press, [etc.], 1898)

Proceedings of the United States National Museum - Smithsonian Institution (Smithsonian Institution Press, [etc.], 1905)

Proceedings of the United States National Museum - Smithsonian Institution (Smithsonian Institution Press, [etc.], 1911)

Proceedings of the United States National Museum - Smithsonian Institution (Smithsonian Institution Press, [etc.], 1934)

Proceedings of the United States National Museum - Smithsonian Institution (Smithsonian Institution Press, [etc.], 1954)

Proceedings of the VIIth International Orthnithological Congress at Amsterdam 1930 - Beaufort, L. F. de (Lieven Ferdinand), 1879 -1968 (C. de Boer Jr, 1931)

Proceedings of the Zoological Society of London - Zoological Society of London. (Academic Press, [etc.], 1858)

Proceedings of the Zoological Society of London - Zoological Society of London. (Academic Press, [etc.], 1859)

Proceedings of the Zoological Society of London - Zoological Society of London. (Academic Press, [etc.], 1860)

Proceedings of the Zoological Society of London - Zoological Society of London. (Academic Press, [etc.], 1863)

Proceedings of the Zoological Society of London - Zoological Society of London. (Academic Press, [etc.], 1871)

Proceedings of the Zoological Society of London - Zoological Society of London. (Academic Press, [etc.], 1872)

Proceedings of the Zoological Society of London - Zoological Society of London. (Academic Press, [etc.], 1874)

Proceedings of the Zoological Society of London - Zoological Society of London. (Academic Press, [etc.], 1877)

Proceedings of the Zoological Society of London - Zoological Society of London. (Academic Press, [etc.], 1878)

Proceedings of the Zoological Society of London - Zoological Society of London. (Academic Press, [etc.], 1888)

Proceedings of the Zoological Society of London - Zoological Society of London. (Academic Press, [etc.], 1911)

Proceedings of the Zoological Society of London - Zoological Society of London. (Academic Press, [etc.], 1923)

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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, 1848)

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, 1873)

Provisional check list of birds of East Africa and Uganda - Van Someren, Victor Gurner Logan, 1886 -1976 ([East Africa and Uganda Natural History Society], 1917)

Ptaki - Lemberg. Muzeum imienia Dzieduszyckich. (Z I Zwiazkowij drukarni, 1880)

[Publications] - Bureau of Government Laboratories - Philippines. Bureau of Government Laboratories. (Bureau of Public Printing, 1906)

Rambles of a naturalist in Egypt & other countries. With an analysis of the claims of certain foreign birds to be considered British, and other ornithological notes - Gurney, J. H. (John Henry), 1848 -1922 (Jarrold, 1876)

Recensio avium in academici liberi baronis de Mueller ornithologico museo stuttgardiano collectarum - Calwer, C. G. (Carl Gustav), 1821 -1874 (Officinae Regiae, 1854)

A record of plants collected in Southern Rhodesia; arramged on Engler's system - Eyles, Fred (1916)

Record of Proceedings / Cleveland Naturalists' Field Club - Cleveland Naturalists' Field Club. (1899)

The Record of zoological literature (J. van Voorst, 1868)

Records of the Australian Museum - Australian Museum (Printed by order of the Trustees, 2016)

Records of the Botanical Survey of India - Botanical Survey of India. (Office of Supt. of Govt. Print., India, 1893)

Records of the Botanical Survey of India - Botanical Survey of India. (Office of Supt. of Govt. Print., India, 1903)

Reise der österreichischen Fregatte Novara um die Erde in den Jahren 1857, 1858, 1859 unter den Befehlen des Commodore B. von Wüllerstorf-Urbair - Österreichische Akademie der Wissenschaften. (Kaiserlich-Königliche Hof- und Staatsdruckerei; in Commission bei K. Gerold's Sohn, 1868)

Reise der österreichischen Fregatte Novara um die Erde in den Jahren 1857, 1858, 1859 unter den Befehlen des Commodore B. von Wüllerstorf-Urbair - Österreichische Akademie der Wissenschaften. (Kaiserlich-Königliche Hof- und Staatsdruckerei; in Commission bei K. Gerold's Sohn, 1869)

Reise der österreichischen Fregatte Novara um die Erde in den Jahren 1857, 1858, 1859 unter den Befehlen des Commodore B. von Wüllerstorf-Urbair - Österreichische Akademie der Wissenschaften. (Kaiserlich-Königliche Hof- und Staatsdruckerei; in Commission bei K. Gerold's Sohn, 1865)

Reise in Nordost-Afrika. Schilderungen aus dem Gebiete der Beni Amer und Habab nebst zoologischen Skizzen und einem Führer für Jagdreisende - Heuglin, Theodor von, 1824 -1876 (G. Westermann, 1877)

Reise in Ostafrika in den Jahren 1903-1905 : mit Mitteln der Hermann und Elise geb. Heckmann Wentzel-Stiftung : Wissenschaftliche Ergebnisse - Voeltzkow, Alfred, 1860 -1946 (E. Schweizerbartsche Verlagsbuchhandlung, 1923)

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)

Remarques sur l'ornithologie de l'État indépendant du Congo : suivies d'une liste des espèces recueillies jusqu'ici dans cet état - Dubois, Alphonse, 1839 -1921. ([s.n, 1905)

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)

Repertorium botanices systematicae - Walpers, Wilhelm Gerhard, 1816 -1853 (Sumtibus Friderici Hofmeister, 1844)

Repertorium botanices systematicae - Walpers, Wilhelm Gerhard, 1816 -1853 (Sumtibus Friderici Hofmeister, 1846)

Repertorium specierum novarum regni vegetabilis (Selbstverlag des Herausgebers, 1912)

Report of the ... Australasian Association for the Advancement of Science - Australasian Association for the Advancement of Science. (The Association, 1909)

Report of the (Free) Public Library, Museum (Liverpool) - Liverpool (England). Free Public Library. Museum (1905)

Report on the migration of birds - Harvie-Brown, J. A. (John Alexander), 1844 -1916 (1885)

Report on the migration of birds - Harvie-Brown, J. A. (John Alexander), 1844 -1916 (1886)

Report on the migration of birds - Harvie-Brown, J. A. (John Alexander), 1844 -1916 (1887)

Report on the migration of birds in the spring and autumn of 1885 - Harvie-Brown, J. A. (John Alexander), 1844 -1916 (M' Farlane and Erskine, 1885)

Resultate der Wissenschaftlichen Erforschung des Balatonsees - Hungary. Földmm̋uvelésügyi Minisztérium. (E. Hölzel, 1897)

Results of the first Joint US-USSR Central Pacific Expedition (BERPAC) : Autumn 1988 - U.S. Fish; Wildlife Service (U.S. Fish and Wildlife Service, 1992)

A revised catalogue of the birds of China and its islands, with descriptions of new species, references to former notes, and occasional remarks - Swinhoe, Robert, 1836 -1877 (1871)

Revisio generum plantarum vascularium omnium atque cellularium multarum secundum leges nomenclaturae internationales cum enumeratione plantarum exoticarum in itinere mundi collectarum, mit erläuterungen - Kuntze, Otto, 1843 -1907 (A. Felix [etc., etc.], 1891)

Revisio generum plantarum:vascularium omnium atque cellularium multarum secundum leges nomenclaturae internationales cum enumeratione plantarum exoticarum in itinere mundi collectarum ... - Kuntze, Otto, 1843 -1907 (A. Felix [etc.], 1891)

Revue critique de l'Ornithologie Européenne de M. De Selys Longchamps - Bonaparte, Charles-Lucien, 1803 -1857 (1850)

Revue française d'ornithologie - Société ornithologique et mammalogique de France. (L. Denise, 1911)

Revue française d'ornithologie - Société ornithologique et mammalogique de France. (L. Denise, 1909)

Revue française d'ornithologie - Société ornithologique et mammalogique de France. (L. Denise, 1915)