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

Pacific coast avifauna - Cooper Ornithological Club. (Cooper Ornithological Club, 1902)

Pacific coast avifauna - Cooper Ornithological Club. (Cooper Ornithological Club, 1904)

Pacific coast avifauna - Cooper Ornithological Club. (Cooper Ornithological Club, 1913)

Pacific coast avifauna - Cooper Ornithological Club. (Cooper Ornithological Club, 1914)

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

Pacific coast avifauna - Cooper Ornithological Club. (Cooper Ornithological Club, 1919)

Panama, 1944 : reference materials, addresses of contacts, passport photographs, news clippings, and memorabilia - Wetmore, Alexander, 1886 -1978 (1944)

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, 1945)

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)

Papers from the Hopkins-Stanford Galapagos expedition, 1898-1899 - Hopkins-Stanford Galapagos Expedition, 1898-99. (The Academy, 1901)

Parasitology - British Society for Parasitology. (Cambridge University Press, 1916)

Part I. Palæontology - Hall, James, 1811 -1898 (Govt. print. off, 1877)

P.D. Skaar's Montana bird distribution - Skaar, Palmer David. (Montana Natural Heritage Program, 2003)

Pennsylvania bird life; a manual of the birds of Pennsylvania; treating especially of their food, from examinations of several thousand stomachs, made during all seasons of the year, with descriptions of the birds, their nests, eggs and habits - Warren, Benjamin Harry, 1858 -1926 (Penn'a., Pub by the author, 1892)

Perú: Cordillera Escalera-Loreto - Stotz, Douglas F. (Douglas Forrester), 1956 - (The Field Museum, Science and Education, 2014)

Perú : Tapiche-Blanco - Field Museum of Natural History. (The Field Museum, 2015)

A phylogeny of the kingbirds and their allies - Lanyon, Wesley E. (American Museum of Natural History, 1984)

A phylogeny of the thirty-three genera in the Empidonax assemblage of tyrant flycatchers - Lanyon, Wesley E. (American Museum of Natural History, 1986)

A phylogeny of the thirty-two genera in the Elaenia assemblage of tyrant flycatchers - Lanyon, Wesley E. (American Museum of Natural History, 1988)

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

Phytoneuron (Guy L. Nesom, 2013)

Pocket key of the birds of the northern United States, east of the Rocky Mountains - Apgar, A. C. (Austin Craig), 1838 -1908 (J.L. Murphy Pub. Co., Printers, 1893)

A popular handbook of the birds of Canada and the United States - Nuttall, Thomas, 1786 -1859 (Musson Book Co, 1903)

A popular handbook of the birds of the United States and Canada - Nuttall, Thomas, 1786 -1859 (Little, Brown, 1903)

A popular handbook of the birds of the United States and Canada - Nuttall, Thomas, 1786 -1859 (Little, Brown, 1905)

The Popular science monthly - Harry Houdini Collection (Library of Congress) (Popular Science Pub. Co., etc, 1893)

The Popular science monthly - Harry Houdini Collection (Library of Congress) (Popular Science Pub. Co., etc, 1872)

Postilla - Peabody Museum of Natural History. (Peabody Museum of Natural History, 1962)

Postilla - Peabody Museum of Natural History. (Peabody Museum of Natural History, 1965)

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

A preliminary catalog of the birds of Missouri - Widmann, Otto (Academy of Sciences 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)

A preliminary report on the sugarbeet wireworm - Graf, J. E. (John Enos), 1889 - (Govt. print. off, 1914)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1859)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1863)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1864)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1865)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1866)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1868)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1872)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1875)

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

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1890)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1892)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1895)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1896)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1898)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1904)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1905)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1907)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1913)

Proceedings of the Academy of Natural Sciences of Philadelphia - Academy of Natural Sciences of Philadelphia. (Academy of Natural Sciences of Philadelphia, 1841)