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 Fragmente : aus den Handschriften - Petényi, János Salamon, 1799 -1855 (F.E. Kr, 1905)

Ornithologische Monatsberichte (Verlag von R. Friedländer & Sohn, 1893)

Ornithologische Monatsberichte (Verlag von R. Friedländer & Sohn, 1895)

Ornithologische Monatsberichte (Verlag von R. Friedländer & Sohn, 1896)

Ornithologische Monatsberichte (Verlag von R. Friedländer & Sohn, 1898)

Ornithologische Monatsberichte (Verlag von R. Friedländer & Sohn, 1899)

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

Ornithologische Monatsberichte (Verlag von R. Friedländer & Sohn, 1902)

Ornithologische Monatsberichte (Verlag von R. Friedländer & Sohn, 1903)

Ornithologische Monatsberichte (Verlag von R. Friedländer & Sohn, 1905)

Ornithologische Monatsberichte (Verlag von R. Friedländer & Sohn, 1906)

Ornithologische Monatsberichte (Verlag von R. Friedländer & Sohn, 1907)

Ornithologische Monatsberichte (Verlag von R. Friedländer & Sohn, 1912)

Ornithologische Monatsschrift - Deutscher Verein zum Schutze der Vogelwelt. (Kommissions-Verlag der Creutschen Verlagsbuchhandlung, 1894)

Ornithologische Monatsschrift - Deutscher Verein zum Schutze der Vogelwelt. (Kommissions-Verlag der Creutschen Verlagsbuchhandlung, 1896)

Ornithologische Monatsschrift - Deutscher Verein zum Schutze der Vogelwelt. (Kommissions-Verlag der Creutschen Verlagsbuchhandlung, 1901)

Ornithologische Monatsschrift - Deutscher Verein zum Schutze der Vogelwelt. (Kommissions-Verlag der Creutschen Verlagsbuchhandlung, 1902)

Ornithologische Monatsschrift - Deutscher Verein zum Schutze der Vogelwelt. (Kommissions-Verlag der Creutschen Verlagsbuchhandlung, 1914)

Ein ornithologischer Ausflug nach den Seen Saissan-nor und Marka-kul (in West-Sibirien) im Jahre 1909 - Poljakov, G. I. (1912)

Ornithologischer Beitrag zur Fauna Madagascar's. Mit Berücksichtigung der Inseln Mayotta, Nossi-Bé und St. Marie, sowie der Mascarenen und Seychellen - Hartlaub, Gustav, 1814 -1900 (C. Schünemann, 1861)

Ornithologisches Centralblatt (1881)

Ornithologisches Jahrbuch (V. Tschusi, 1890)

Ornithologisches Jahrbuch (V. Tschusi, 1900)

Ornithologisches Jahrbuch (V. Tschusi, 1902)

Ornithologisches Jahrbuch (V. Tschusi, 1905)

Ornithologisches Jahrbuch (V. Tschusi, 1906)

Ornithologisches Jahrbuch (V. Tschusi, 1907)

Ornithologisches Jahrbuch (V. Tschusi, 1910)

Ornithologisches Jahrbuch (V. Tschusi, 1911)

Ornithologisches Jahrbuch (V. Tschusi, 1914)

The Ornithologist and oölogist (1881)

The Ornithologist and oölogist (1889)

The ornithology of Illinois - Ridgway, Robert, 1850 -1929 (H. W. Rokker, printer, 1889)

Ornitologia della Papuasia e delle Molucche - Salvadori, Tommaso, 1835 -1923 (G.B. Paravia, 1889)

Ornitologia della Papuasia e delle Molucche - Salvadori, Tommaso, 1835 -1923 (G.B. Paravia, 1880)

The Osprey (The Osprey Co, 1900)

O.S.U. naturalist - Ohio State University. Biological Club. (Biological Club of Ohio State University, 1901)

Our common birds and how to know them - Grant, John Beveridge (C. Scribner's sons, 1895)

Our native birds of song and beauty, being a complete history of all the songbirds, flycatchers, hummingbirds, swifts, goatsuckers, woodpeckers, kingfishers, trogons, cuckoos, and parrots, of North America - Nehrling, Henry, 1853 -1929 (G. Brumder, 1893)

Our northern and eastern birds : containing descriptions of the birds of the northern and eastern states and British provinces; together with a history of their habits, times of arrival and departure, their distribution, food, song, time of breeding, and a careful and accurate description of their nests and eggs - Samuels, Edward A. (Edward Augustus), 1836 -1908 (R. Worthington, 1883)

Our search for a wilderness; an account of two ornithological expeditions to Venezuela and to British Guiana - Beebe, William, 1877 -1962 (Constable, 1910)

Our search for a wilderness; an account of two ornithological expeditions to Venezuela and to British Guiana - Beebe, William, 1877 -1962 (H. Holt and company, 1910)

Our search for a wilderness : an account of two ornithological expeditions to Venezuela and to British Guiana - Beebe, William, 1877 -1962 (Holt, 1910)

Outlines of American ornithology : part 1, Land birds - Baird, Spencer Fullerton, 1823 -1887 (Little, Brown, 1873)

Oversigt af Christiania omegns ornithologiske fauna - Collett, Robert, 1842 -1913 (J. Dahl, 1864)

Pacific coast avifauna - Cooper Ornithological Club. (Cooper Ornithological Club, 1909)

Pacific coast avifauna - Cooper Ornithological Club. (Cooper Ornithological Club, 1912)

Pacific coast avifauna - Cooper Ornithological Club. (Cooper Ornithological Club, 1917)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1916)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1918)

Pamphlets on forestry in West Virginia (1900)

Papéis avulsos do Departamento de Zoologia - São Paulo Departamento de Zoologia (A Secretaria, 1943)

Papéis avulsos do Departamento de Zoologia - São Paulo Departamento de Zoologia (A Secretaria, 1944)

Papéis avulsos do Departamento de Zoologia - São Paulo Departamento de Zoologia (A Secretaria, 1947)

Papéis avulsos do Departamento de Zoologia - São Paulo Departamento de Zoologia (A Secretaria, 1948)

Papéis avulsos do Departamento de Zoologia - São Paulo Departamento de Zoologia (A Secretaria, 1952)

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Per una classificazione elementare dei Passercei, Rampicanti e Trogoni, raccolta e ordinamento di alcuni caratteri - Cavazza, Filippo. (Tipografia di Paolo Neri, 1909)

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Perú, Medio Putumayo-Algodón - Stotz, Douglas F. (Douglas Forrester), 1956 - (Field Museum of Natural History, 2016)

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Philippine birds - Du Pont, John E. (John Eleuthère), 1938 -2010 ([Delaware Museum of Natural History], 1971)

The Phoenix - Jennings, Michael C. (M.C. Jennings, 2008)

Photoperiodism and related phenomena in plants and animals; proceedings - Withrow, Robert B. 1904 -1958 (1959)

Physiology of the temperature of birds - Baldwin, Samuel Prentiss, 1868 -1938 (Cleveland Museum of Natural History, 1932)

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Postilla - Peabody Museum of Natural History. (Peabody Museum of Natural History, 1968)

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A preliminary catalog of the birds of Missouri - Widmann, Otto (Academy of Science of St. Louis, 1907)

A preliminary list of the birds of Wayne County, Ohio - Oberholser, Harry C. (Harry Church), 1870 -1963 (Westbote Co., State Printers, 1896)

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

Proceedings of the International Ornithological Congress (Australian Academy of Science [etc.], 1929)

Proceedings of the International Ornithological Congress (Australian Academy of Science [etc.], 1938)

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)