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The passenger pigeon, its natural history and extinction - Schorger, A. W. (Arlie William), 1884 -1972 (University of Wisconsin Press, 1955)

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Pedanii Dioscoridis anazerbei De materia medica libri quinque : ad fidem cadicum manuscriptorum - Sprengel, Kurt Polycarp Joachim, 1766 -1833 (Cnobloch, C. (Carl), 1778-1834, 1829)

Pehr Kalms Resa till Norra Amerika - Kalm, Pehr, 1716 -1779 (Tidnings & tryckeri-aktiebolagets tryckeri, 1904)

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Pestmegye és tájéka viránya - Gönczy, Pál, 1817 -1892 (Ráth mór Bizománya, 1864)

Peter Artedi : a bicentenary memoir : written on behalf of the Swedish Royal Academy of Science - Lönnberg, Einar, 1865 -1942 (Almquist & Wiksells Boktr, 1905)

Petite faune entomologique du Canada : précédée d'un traité élémentaire d'entomologie - Provancher, L. (Léon), 1820 -1892 (C. Darveau, 1883)

Petites nouvelles entomologiques (E. Deyrolle, 1869)

Petri Artedi ... Ichthyologia sive opera omnia de piscibus, scilicet: Bibliotheca ichthyologica. Philosophia ichthyologica. Genera piscium. Synonymia specierum. Descriptiones specierum. Omnia in hoc genere perfectiora, quam antea ulla - Linné, Carl von, 1707 -1778 (apud Conradum Wishoff, 1738)

Petri Artedi ... Ichthyologia: sive, opera omnia de piscibus, scilicet: Bibliotheca ichthyologica. Philosophia ichthyologica. Genera piscium. Synonymia specierum. Descriptiones specierum. Omnia in hoc genere perfectiora, quam antea ulla - Artedi, Peter, 1705 -1735 (Apud Conradum Wishoff, 1738)

Petri Artedi renovati pars I. et II. [III-V] : i.e. bibliotheca et philosophia ichthyologica - Walbaum, Johann Julius, 1724 -1799 (impensis A. F. Röse, 1788)

Petri Artedi renovati pars I. et II. [III-V] : i.e. bibliotheca et philosophia ichthyologica - Linné, Carl von, 1707 -1778 (Impensis A.F. Röse, 1793)

Die Pflanzendecke Österreich-Ungarns. Auf Grund fremder und eigener Forschungen geschildert - Hayek, August von, 1871 -1928 (F. Deuticke, 1914)