Official lists and indexes of names and works in zoology - International Commission on Zoological Nomenclature (ICZN, 1987)

Öfversigt af Finska vetenskaps-societetens förhandlingar - Suomen Tiedeseura (s.n.], 1853)

Öfversigt af Finska vetenskaps-societetens förhandlingar - Suomen Tiedeseura (s.n.], 1864)

Öfversigt af Finska vetenskaps-societetens förhandlingar - Suomen Tiedeseura (s.n.], 1865)

Öfversigt af Kongl. Vetenskaps-akademiens forhandlingar - Kungl. Svenska vetenskapsakademien. (P. A. Norstedt & Söner, 1845)

Öfversigt af Kongl. Vetenskaps-akademiens forhandlingar - Kungl. Svenska vetenskapsakademien. (P. A. Norstedt & Söner, 1850)

Öfversigt af Kongl. Vetenskaps-akademiens forhandlingar - Kungl. Svenska vetenskapsakademien. (P. A. Norstedt & Söner, 1851)

Öfversigt af Kongl. Vetenskaps-akademiens forhandlingar - Kungl. Svenska vetenskapsakademien. (P. A. Norstedt & Söner, 1859)

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, 1863)

Öfversigt af Kongl. Vetenskaps-akademiens forhandlingar - Kungl. Svenska vetenskapsakademien. (P. A. Norstedt & Söner, 1868)

Öfversigt af Kongl. Vetenskaps-akademiens forhandlingar - Kungl. Svenska vetenskapsakademien. (P. A. Norstedt & Söner, 1869)

Öfversigt af Kongl. Vetenskaps-akademiens forhandlingar - Kungl. Svenska vetenskapsakademien. (P. A. Norstedt & Söner, 1871)

Öfversigt af Kongl. Vetenskaps-akademiens forhandlingar - Kungl. Svenska vetenskapsakademien. (P. A. Norstedt & Söner, 1875)

Ohrknorpel und äusseres ohr der Säugetiere; eine vergleichend-anatomische Untersuchung - Boas, J. E. V. (Johan Erik Vesti), 1855 -1935 ([Nielsen & Lydiche (A. Simmelkiær)], 1912)

Okens Lehrbuch der Naturgeschichte - Oken, Lorenz, 1779 -1851 (Bei Carl Heinrich Reclam, 1815)

Okens Lehrbuch der Naturgeschichte - Oken, Lorenz, 1779 -1851 (Bei Carl Heinrich Reclam, 1816)

Old bones : or, Notes for young naturalists - Brooks, Vincent, 1815? -1885 (Robert Hardwicke, 1861)

Om Limfjordens tidligere og nuværende marine fauna, med særligt hensyn til bløddyraunaen - Denmark. Ministeriet for kirke- og undervisningsvæsenet. (Gyldendal, 1884)

Om slägtet Sorex, med några nya arters beskrifning - Sundevall, Carl J., 1801 -1875 (Kungliga Vetenskapsakademien, 1842)

On mammalian descent the Hunterian Lectures for 1884 : being nine lectures delivered in the theatre of the Royal College of Surgeons during February, 1884 - Parker, William Kitchen William Kitchen Parker 1823 -1890 (C. Griffin, 1885)

On mammalian descent; the Hunterian Lectures for 1884; being nine lectures delivered in the theatre of the Royal College of Surgeons during February, 1884 - Parker, William Kitchen William Kitchen Parker 1823 -1890 (Charles Griffin, 1885)

On "retrogression" in the evolution of the Phocinae and phylogenetic affinities of the monk seals - Wyss, André R. (American Museum of Natural History, 1988)

On some marine Invertebrata dredged or otherwise collected by Dr. G.M. Dawson, in 1885, on the coast of British Columbia; with a supplementary list of a few land and fresh water shells, fishes, birds, etc., from the same region - Whiteaves, Joseph Frederick, 1835 -1909 (Dawson brothers, 1887)

On the anatomy of vertebrates - Owen, Richard, 1804 -1892 (Longmans, Green, 1866)

On the anatomy of vertebrates ... - Owen, Richard, 1804 -1892 (Longmans, Green and Co, 1866)

On the Apocynaceae of South America, with some preliminary remarks on the whole family ... - Miers, John, 1789 -1879 (Williams and Norgate, 1878)

On the fauna and flora of the west of Scotland. Meeting at Glasgow, September, 1876 - British Association for the Advancement of Science. (Blackie, 1876)

On the habits and instincts of animals - Swainson, William, 1789 -1855 (Printed for Longman, Orme, Brown, Green, & Longmans, 1840)

On the morphology of the duck and the auk tribes - Parker, William Kitchen William Kitchen Parker 1823 -1890 (s.n.], 1890)

On the place of fish in a hard-working diet : with notes on the use of fish in former times - Mitchell, William Stephen, 1840 -1892 (W. Clowes and Sons, 1884)

On the power, wisdom, and goodness of God : as manifested in the creation of animals, and in their history, habits, and instincts - Jones, Thomas Rymer, 1810 -1880 (H.G. Bohn, 1853)

On the power, wisdom and goodness of God, as manifested in the creation of animals, and in their history, habits and instincts - Kirby, William, 1759 -1850 (Carey, Lea & Blanchard, 1836)

On the power, wisdom and goodness of God as manifested in the creation of animals and in their history, habits and instincts - Kirby, William, 1759 -1850 (W. Pickering, 1835)

Onomasticon zoicon, plerorumque animalium differentias & nomina propria pluribus linguis exponens : cui accedunt Mantissa anatomica, et quaedam De variis fossilium generibus - Charleton, Walter, 1619 -1707 (Apud Jacobum Allestry ..., 1668)

Onomatologia Anatomica. Geschichte und Kritik der anatomischen Sprache der Gegenwart, mit besonderer Berücksichtigung ihrer Barbarismen, Widersinnigkeiten, Tropen und grammatikalischen Fehler - Hyrtl, Joseph, 1811 -1894 (W. Braumüller, 1880)

Ontdekkingsreis in de Zuid-Zee en naar de Berings-Straat in de jaren 1815, 1816, 1817 en 1818 onder het bevel van Otto von Kotzebue - Chamisso, Adelbert von, 1781 -1838 (J. van der Hey, 1822)

Die Ontogenie der Primatenzähne : versuch einer Lösung der Gebissprobleme - Bolk, L. (Louis), 1866 -1930 (Verlag von Gustav Fischer, 1913)

Die Ontogenie der Primatenzähne - Bolk, L. (Louis), 1866 -1930 (G. Fischer, 1913)

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, 1947)

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, 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, 1954)

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)

Oppian, Colluthus, Tryphiodorus, with an English translation by A.W. Mair - Colluthus, of Lycopolis. (W. Heinemann, 1928)

Opuscoli scientifici d'entomologia, di fisica e d'agricoltura - Termeyer, Ramón María, 1737 -1814 (Nella Stamperia del Giornale italico di Carlo Dova, contrada S. Rafaello, num. 998, 1807)

The orders of mammals - Gregory, William K. (William King), 1876 -1970 (The Trustees, 1910)

Ordre naturel des oursins de mer et fossiles : avec des observations sur les piquans des oursins de mer, et quelques remarques sur les bélemnites - Klein, Jacob Theodor, 1685 -1759 (Cl. J.B. Bauche, 1754)

The Oregon naturalist (Naturalist Pub. Co, 1896)

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

Ornithologisches Jahrbuch (V. Tschusi, 1901)

Ornithologiske bemaerkninger til Norges fauna ... (Indberetning til det Academiske collegium ved det Kongelige Frederiks universitet - Collett, Robert, 1842 -1913 (J. Dahl, 1871)

The ornithologist's guide to the islands of Orkney and Shetland - Hullmandel, Charles Joseph, 1789 -1850 (Printed by Richard Taylor, Red Lion Court, Fleet Street, and published by the author, 31, George Street, Hull, 1837)

Ostéographie, ou, Description iconographique comparée du squelette et du système dentaire des Mammifères récents et fossiles : pour servir de base à la zoologie et à la géologie - Blainville, H.-M. Ducrotay de (Henri-Marie Ducrotay), 1777 -1850 (J.B. Baillière et fils, 1839)