Occasional papers of the California Academy of Sciences - California Academy of Sciences (California Academy of Sciences, 1893)

Occasional papers of the Museum of Natural History, the University of Kansas - University of Kansas. Museum of Natural History. (The University, 1991)

Occasional papers of the Museum of Natural History, the University of Kansas - University of Kansas. Museum of Natural History. (The University, 1994)

Öfversigt af Finska vetenskaps-societetens förhandlingar - Suomen Tiedeseura (s.n.], 1910)

Oil spill sensitivity of the western Indian Ocean islands: coastal data from the Comoros Islands, Madagascar, Mauritius, Reunion and the Seychelles - Green, Edmund P. (Edmund Peter) 1965 - (WCMC, 1998)

L'Oiseau et la Revue francaise d'ornithologie - Société ornithologique de France. (Société ornithologique de France, 1954)

L'Oiseau et la Revue francaise d'ornithologie - Société ornithologique de France. (Société ornithologique de France, 1957)

L'Oiseau et la Revue francaise d'ornithologie - Société ornithologique de France. (Société ornithologique de France, 1964)

L'Oiseau et la Revue francaise d'ornithologie - Société ornithologique de France. (Société ornithologique de France, 1965)

L'Oiseau et la Revue francaise d'ornithologie - Société ornithologique de France. (Société ornithologique de France, 1973)

L'Oiseau et la Revue francaise d'ornithologie - Société ornithologique de France. (Société ornithologique de France, 1975)

L'Oiseau et la Revue francaise d'ornithologie - Société ornithologique de France. (Société ornithologique de France, 1976)

L'Oiseau et la Revue francaise d'ornithologie - Société ornithologique de France. (Société ornithologique de France, 1978)

L'Oiseau et la Revue francaise d'ornithologie - Société ornithologique de France. (Société ornithologique de France, 1988)

Les oiseaux de l'est du Canada - Taverner, P. A. (Percy Algernon), 1875 -1947 (F.A. Acland, 1922)

Les oiseaux de la Suisse (Catalogue des oiseaux de la Suisse de V. Fatio et Th. Studer) élaboré par ordre du Département fédéral de l'intérieur (Inspection des forêts, chasse et pêche) - Fatio, Victor, 1838 -1906 (1889)

Oiseaux - Fédération des sociétés françaises de sciences naturelles. Office central de faunistique. (P. Lechevalier, 1921)

On the intestinal tract of birds; with remarks on the valuation and nomenclature of zoological characters - Mitchell, P. Chalmers Sir, (Peter Chalmers), 1864 -1945 (1901)

On the natural history and classification of birds - Swainson, William, 1789 -1855 (John Taylor, 1836)

The Oölogist for the student of birds, their nests and eggs - Lattin, Frank H. (Frank H. Lattin, 1888)

The Oölogist for the student of birds, their nests and eggs - Lattin, Frank H. (Frank H. Lattin, 1889)

The Oölogist for the student of birds, their nests and eggs - Lattin, Frank H. (Frank H. Lattin, 1891)

The Oölogist for the student of birds, their nests and eggs - Lattin, Frank H. (Frank H. Lattin, 1893)

The Oölogist for the student of birds, their nests and eggs - Lattin, Frank H. (Frank H. Lattin, 1894)

The Oölogist for the student of birds, their nests and eggs - Lattin, Frank H. (Frank H. Lattin, 1907)

Oologia neerlandica : eggs of birds breeding in the Netherlands - Lechner, Arnold Anthon van Pelt (Nijhoff, 1911)

The origin of the fittest; essays on evolution - Cope, E. D. (Edward Drinker), 1840 -1897 (D. Appleton, 1887)

Ornis - International Ornithological Committee. (Carl Gerold's Sohn, 1885)

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

Ornis - International Ornithological Committee. (Carl Gerold's Sohn, 1887)

Ornis - International Ornithological Committee. (Carl Gerold's Sohn, 1888)

Ornis - International Ornithological Committee. (Carl Gerold's Sohn, 1891)

Ornis - International Ornithological Committee. (Carl Gerold's Sohn, 1904)

Ornis Carinthiae. Die Vögel Kärntens. Verzeichniss der bis jetzt in Kärnten beobachteten Vögel, nebst bemerkungen über deren zug, Lebensweise, locale Eigenthümlichkeiten etc. etc - Keller, Franz Carl, 1847 -1907 (Druck von Ferd. v. Kleinmayr, 1890)

Ornis Caucasica. Die Vogelwelt des Kaukasus : systematisch und biologisch-geographisch beschrieben - Radde, Gustav, 1831 -1903 (Verlag von Theodor Fischer, 1884)

Ornithological bibliography - Coues, Elliott, 1842 -1899 (Geological Survey [etc.], 1878)

Ornithological gazetteer of Argentina - Paynter, Raymond A. Jr. (Obtainable from Bird Dept., Museum of Comparative Zoology, Harvard University, 1995)

Ornithological gazetteer of Brazil - Traylor, Melvin A. (Melvin Alvah), 1915 -2008 (Obtainable from Bird Dept., Museum of Comparative Zoology, Harvard University, 1991)

Ornithological gazetteer of Chile - Paynter, Raymond A. Jr. (Bird Dept., Museum of Comparative Zoology, Harvard University, 1988)

Ornithological gazetteer of Colombia - Paynter, Raymond A. Jr. (Bird Dept., Museum of Comparative Zoology, Harvard University, 1997)

Ornithological gazetteer of Uruguay - Paynter, Raymond A. Jr. (Obtainable from Bird Dept., Museum of Comparative Zoology, Harvard University, 1994)

Ornithological rambles in Sussex : with a systematic catalogue of the birds of that county, and remarks on their local distribution - Knox, Arthur Edward (J. Van Voorst, 1849)

Ornithological rambles in Sussex: with a systematic catalogue of the birds of that country, and remarks on their local distribution - Knox, Arthur Edward (J. Van Voarst, 1850)

Ornithological science - Nihon Chogakkai (Ornithological Society of Japan, 2002)

Ornithologie d'Angola. Ouvrage publié sous les auspices du Ministere de la Marine et des Colonies - Barbosa du Bocage, J. V. (José Vicente), 1823 -1908 (Imprimerie Nationale, 1881)

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)