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Proceedings of the Rochester Academy of Science - Rochester Academy of Science. (The Academy, 1894)

Proceedings of the Royal Horticultural Society London (Royal Horticultural Society, 1862)

Proceedings of the Royal Horticultural Society London (Royal Horticultural Society, 1866)

Proceedings of the Royal Irish Academy - Royal Irish Academy. (Royal Irish Academy, 1875)

Proceedings of the Royal Irish Academy - Royal Irish Academy. (Royal Irish Academy, 1883)

Proceedings of the Royal Irish Academy - Royal Irish Academy. (Royal Irish Academy, 1884)

Proceedings of the Royal Irish Academy - Royal Irish Academy. (Royal Irish Academy, 1888)

Proceedings of the Royal Irish Academy - Royal Irish Academy. (Royal Irish Academy, 1891)

Proceedings of the Royal Irish Academy - Royal Irish Academy. (Royal Irish Academy, 1901)

Proceedings of the Royal Irish Academy - Royal Irish Academy. (Royal Irish Academy, 1902)

Proceedings of the Royal Irish Academy - Royal Irish Academy. (Royal Irish Academy, 1911)

Proceedings of the Royal Physical Society of Edinburgh - Royal Physical Society of Edinburgh. (The Society, 1874)

Proceedings of the Royal Physical Society of Edinburgh - Royal Physical Society of Edinburgh. (The Society, 1885)

Proceedings of the Royal Society of Edinburgh - Royal Society of Edinburgh. (Royal Society of Edinburgh, 1909)

Proceedings of the Royal Society of Edinburgh - Royal Society of Edinburgh. (Royal Society of Edinburgh, 1915)

Proceedings of the Royal Society of Edinburgh - Royal Society of Edinburgh. (Royal Society of Edinburgh, 1920)

Proceedings of the Royal Society of London - Royal Society (Great Britain) (The Society, 1887)

Proceedings of the Royal Society of London - Royal Society (Great Britain) (The Society, 1899)

Proceedings of the semi-centennial anniversary of the Torrey botanical club, October 18, 19 and 20, 1917 - Torrey Botanical Club. (1918)

Proceedings of the Staten Island Association of Arts and Sciences - Staten Island Association of Arts; Sciences. (The Association, 1906)

Proceedings of the United States National Museum - Smithsonian Institution (Smithsonian Institution Press, [etc.], 1901)

Procès-verbaux - Société Linnéenne de Bordeaux. (1895)

Procès-verbaux - Société Linnéenne de Bordeaux. (1901)

Procès-verbaux - Société Linnéenne de Bordeaux. (1910)

Procès-verbaux - Société Linnéenne de Bordeaux. (1917)

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Procès-verbaux - Société Linnéenne de Bordeaux. (1959)

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Prodrome d'une histoire des végétaux fossiles - Brongniart, Adolphe, 1801 -1876 (F. G. Levrault, 1828)

Prodrome de la flore belge - Wildeman, E. de (Emile), 1866 -1947 (A. Castaigne, 1898)

Prodrome de la flore corse : comprenant les résultats botaniques de six voyages exécutés en Corse sous les auspices de M. Emile Burnat - Briquet, John, 1870 -1931 (Georg, 1910)

Prodrome de la flore du Grand-Duché de Luxembourg - Koltz, J. P. J. (Jean Pierre Joseph), 1827 -1907 (L. Schamburger, 1873)

Prodromus florae mosquensis - Martius, Heinrich von, 1781 -1831 (In Commercio Industriae, 1817)

Prodromus florae stargardiensis : continens plantas in Ducatu Megapolitano-Stargardiensi S. Strelitzensi sponte provenientes - Schultz, Karl Friedrich, 1765 -1837 (sumtibus C. F. E. Spaethen, 1806)

Prodromus florae veronensis - Goiran, A. (Agostino), 1835 -1909 (1882)

Prof. dr. Thom©♭'s Flora von Deutschland, ©sterreich und der Schweiz in wort und bild f©ơr schule und haus - Thomé, Otto W. (Otto Wilhelm), 1840 -1925 (F. E. K©œhler, 1886)

Prof. dr. Thomé's Flora von Deutschland, Österreich und der Schweiz, in wort und bild, für schule und haus ... mit ... - Migula, W. (Walter), 1863 -1938 (1886)

Prof. dr. Thomé's Flora von Deutschland, Österreich und der Schweiz, in wort und bild, für schule und haus ... mit ... - Migula, W. (Walter), 1863 -1938 (1934)

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Pteridologist - British Pteridological Society. (The Society, 1987)

Pteridologist - British Pteridological Society. (The Society, 1988)

Pteridologist - British Pteridological Society. (The Society, 1989)

Pteridologist - British Pteridological Society. (The Society, 1990)

Pteridologist - British Pteridological Society. (The Society, 1996)

Pteridologist - British Pteridological Society. (The Society, 1997)

Pteridologist - British Pteridological Society. (The Society, 1998)

Pteridologist - British Pteridological Society. (The Society, 1999)

Pteridologist - British Pteridological Society. (The Society, 2000)

Pteridologist - British Pteridological Society. (The Society, 2001)

Pteridologist - British Pteridological Society. (The Society, 2002)

Pteridologist - British Pteridological Society. (The Society, 2003)

Pteridologist - British Pteridological Society. (The Society, 2004)

Pteridologist - British Pteridological Society. (The Society, 2005)

Pteridologist - British Pteridological Society. (The Society, 2006)

Pteridologist - British Pteridological Society. (The Society, 2008)

Pteridologist - British Pteridological Society. (The Society, 2009)

Pteridologist - British Pteridological Society. (The Society, 2010)

Pteridologist - British Pteridological Society. (The Society, 2011)

Pteridologist - British Pteridological Society. (The Society, 2012)

Pteridologist - British Pteridological Society. (The Society, 2013)

Pteridologist - British Pteridological Society. (The Society, 1984)

Pteridologist - British Pteridological Society. (The Society, 2015)

Pteridologist - British Pteridological Society. (The Society, 2016)