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, 1939)

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

Ornithologisches Jahrbuch (V. Tschusi, 1909)

The Ornithologist and oölogist (1886)

The Ornithologist and oölogist (1888)

Ornithology - Jardine, William, 1800 -1874 (W.H. Lizars, 1854)

Østgrønlands vegetationsforhold - Hartz, N. (Nikolaj), 1867 -1937 (B. Lunos Kgl. Hof-bogtr, 1895)

The Ottawa naturalist - Ottawa Field-Naturalists' Club (Ottawa Field-Naturalists' Club, 1887)

The Ottawa naturalist - Ottawa Field-Naturalists' Club (Ottawa Field-Naturalists' Club, 1888)

The Ottawa naturalist - Ottawa Field-Naturalists' Club (Ottawa Field-Naturalists' Club, 1890)

The Ottawa naturalist - Ottawa Field-Naturalists' Club (Ottawa Field-Naturalists' Club, 1889)

The Ottawa naturalist - Ottawa Field-Naturalists' Club (Ottawa Field-Naturalists' Club, 1895)

The Ottawa naturalist - Ottawa Field-Naturalists' Club (Ottawa Field-Naturalists' Club, 1900)

The Ottawa naturalist - Ottawa Field-Naturalists' Club (Ottawa Field-Naturalists' Club, 1901)

The Ottawa naturalist - Ottawa Field-Naturalists' Club (Ottawa Field-Naturalists' Club, 1903)

The Ottawa naturalist - Ottawa Field-Naturalists' Club (Ottawa Field-Naturalists' Club, 1904)

The Ottawa naturalist - Ottawa Field-Naturalists' Club (Ottawa Field-Naturalists' Club, 1909)

The Ottawa naturalist - Ottawa Field-Naturalists' Club (Ottawa Field-Naturalists' Club, 1908)

Otwell Iris Fields, Carlinville, Illinois, 1938 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Otwell Iris Fields, 1938)

The Otwell Iris Fields, Carlinville, Illinois, 1939 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Otwell Iris Fields, 1939)

Our common insects. A popular account of the insects of our fields, forests, gardens and houses - Packard, A. S. (Alpheus Spring), 1839 -1905 (Naturalists' Agency, 1873)

Our common insects A popular account of the insects of our fields, forests, gardens, and houses - Packard, A. S. (Alpheus Spring), 1839 -1905 (Estes and Lauriat, 1873)

Our country's fishes and how to know them : a guide to all the fishes of Great Britain - Gordon, W. J. (Simpkin, Hamilton, Kent & Co, 1902)

Our new guide to rose culture : 1930 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (The Dingee & Conard Co, 1930)

The out-door world, or, Young collector's handbook - Furneaux, William S. (Longmans, Green, 1893)

Outlines of entomology - Murtfeldt, Mary Esther, 1848 -1913 (Tribune Printing Company, State Printers and Binders, 1891)

Outlines of entomology - Murtfeldt, Mary Esther, 1848 -1913 (Tribune printing company, state printers and binders, 1891)

Outlines of general zoology - Baird, Spencer Fullerton, 1823 -1887 (Rudolph Garrigue, 1851)

Oversigt over de i arktiske region hidtil fundne lepidoptera - Schøyen, Wilhelm Maribo, 1844 -1918 (Alb. Cammermeyer, 1880)

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, 1884)

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, 1809)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1914)

Pamietnik Fizyjograficzny (Druk K. Kowalewskiego, 1917)

Pamphlets on forestry. Fish and game (1900)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1928)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1933)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1946)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1947)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1948)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1953)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1963)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1966)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1972)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1973)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1974)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1978)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1982)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 1998)

The Pan-Pacific entomologist - Van Duzee, Edward P. (Edward Payson), 1861 -1940 (Pacific Coast Entomological Society, 2002)

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, 1947)

Papilio - Edwards, Henry, 1827 -1891 (New York Entomological Club, 1881)

Papilio - Edwards, Henry, 1827 -1891 (New York Entomological Club, 1882)

Papilio - Edwards, Henry, 1827 -1891 (New York Entomological Club, 1883)

Papilio - Edwards, Henry, 1827 -1891 (New York Entomological Club, 1884)

Les papillons dans la nature : 64 planches en couleurs et monographies - Robert, Paul-A. (Éditions Delachaux and Niestlé, s.a, 1934)

Les Parnassiens de la faune paléarctique - Austaut, Jules Léon. (E. Heyne, 1889)

La Pêche et les poissons : nouveau dictionnaire général des pêches - Duméril, Auguste Henri André, 1812 -1870 (C. Delagrave et cie, 1868)

Peonies and iris - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (L.D. Baker Peony Gardens, 1939)

Peonies and iris - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (L.D. Baker Peony Gardens, 1940)

Peonies and irises - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Home Garden Company, 1935)

Peonies and irises, 1929 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Indian Spring Farms, Inc, 1929)

Peonies, irises, gladiolus - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Indian Spring Farms, Inc, 1931)

Peonies, irises, gladiolus - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Indian Spring Farms, Inc, 1930)

Peonies, irises, poppies : price list, 1936 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (LeGron Floral Co, 1936)

Peonies, irises, poppies : price list, 1937 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (LeGron Floral Co, 1937)

Peonies, irises, poppies : price list, 1938 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (LeGron Floral Co, 1938)

Peonies, irises, poppies : price list, 1939 - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (LeGron Floral Co, 1939)

Peonies, irises, tulips, gladiolus, lilies [catalog] - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Indian Spring Farms, 1926)

Periódico zoológico - Sociedad Entomológica Argentina. (Sociedad Entomica Argentina, 1874)

Pesci - Canestrini, Giovanni, 1835 -1900 (F. Vallardi.[1872], 1872)

Pesticides documentation bulletin - National Agricultural Library (U.S.) (National Agricultural Library, U.S. Dept. of Agriculture, #c 1965-1969, 1965)