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Personal narrative of explorations and incidents in Texas, New Mexico, California, Sonora, and Chihuahua : connected with the United States and Mexican Boundary Commission, during the years 1850, '51, '52, and '53 - Bartlett, John Russell, 1805 -1886 (D. Appleton & Company, 1854)

Petites nouvelles entomologiques (E. Deyrolle, 1869)

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, 1792)

Das Pflanzenreich :regni vegetablilis conspectus - Engler, Adolf, 1844 -1930 (W. Engelmann, 1905)

Das Pflanzenreich :regni vegetablilis conspectus - Engler, Adolf, 1844 -1930 (W. Engelmann, 1907)

Das Pflanzenreich :regni vegetablilis conspectus - Engler, Adolf, 1844 -1930 (W. Engelmann, 1909)

Das Pflanzenreich :regni vegetablilis conspectus - Engler, Adolf, 1844 -1930 (W. Engelmann, 1910)

Das Pflanzenreich :regni vegetablilis conspectus - Engler, Adolf, 1844 -1930 (W. Engelmann, 1928)

Das Pflanzenreich :regni vegetablilis conspectus - Engler, Adolf, 1844 -1930 (W. Engelmann, 1931)

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Phylogeny of the Pelecypoda : the Aviculidae and their allies - Jackson, Robert Tracy, 1861 -1948 (Boston Society of Natural History, 1890)

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Physis - Sociedad Argentina de Ciencias Naturales. (Asociación Argentina de Ciencias Naturales [etc.], 1915)

Physis - Sociedad Argentina de Ciencias Naturales. (Asociación Argentina de Ciencias Naturales [etc.], 1916)

Physis - Sociedad Argentina de Ciencias Naturales. (Asociación Argentina de Ciencias Naturales [etc.], 1918)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1978)

Phytoneuron (Guy L. Nesom, 2010)

Pinax Theatri botanici Caspari Bauhini : ... sive Index in Theophrasti, Dioscoridis, Plinii et botanicorum qui à seculo scripserunt opera: plantarum circiter sex millium ab ipsis exhibitarum nomina cum earundem synonymiis & differentiis methodicè secundùm earum & genera & species proponens. Opus XL. annorum hactenus non editum summoperè expetitum & ad auctores intelligendos plurimùm faciens ... - Bauhin, Caspar, 1560 -1624 (sumptibus et typis Ludovici Regis, 1623)

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Plant life of Alabama, an account of the distribution, modes of association, and adaptations of the flora of Alabama, together with a systematic catalogue of the plants growing in the state - Mohr, Charles (Charles Theodore), 1824 -1901 (Brown printing co, 1901)

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Popular gardening and fruit growing; An illustrated periodical devoted to horticulture in all its branches (Popular gardening publishing company, 1888)

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Primera reunión del Congreso científico latino americano celebrada en Buenos Aires del 10 al 20 de abril de 1898 por iniciativa de la Sociedad científica argentina... - Congreso Científico Latino Americano Buenos Aires, Argentina) 1898 - (Compañia sud-americana de billetes de banco, 1898)

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