Nuova flora analitica d'Italia, contenente la descrizione delle piante vascolari indigene inselvatichite e largamente coltivate in Italia - Fiori, Adriano 1865 -1950 (Tipografia di M. Ricci, 1923)

Nuova flora analitica d'Italia, contenente la descrizione delle piante vascolari indigene inselvatichite e largamente coltivate in Italia - Fiori, Adriano 1865 -1950 (Tipografia di M. Ricci, 1925)

The nursery-book; a complete guide to the multiplication of plants - Bailey, L. H. (Liberty Hyde), 1858 -1954 (The Macmillan Company, 1901)

The nursery-manual; a complete guide to the multiplication of plants - Bailey, L. H. (Liberty Hyde), 1858 -1954 (Macmillan, 1920)

Nya botaniska notiser ([A. Bonniers Förlag], 1856)

Nyt magazin for naturvidenskaberne - Physiographiske forening i Christiania. (Johan Dahl, 1877)

Nyt magazin for naturvidenskaberne - Physiographiske forening i Christiania. (Johan Dahl, 1907)

Nyt magazin for naturvidenskaberne - Physiographiske forening i Christiania. (Johan Dahl, 1911)

Nyt magazin for naturvidenskaberne - Physiographiske forening i Christiania. (Johan Dahl, 1919)

Observations on the habits of some solitary wasps of Texas - Hartman, Carl Gottfried, 1879 -1968 (The University of Texas, 1905)

Observations sur les hyménoptères d'Europe de la famille des fouisseurs - Vanderlinden, Pierre Léonard, 1797 -1831 (M. Hayez, 1829)

Observations sur les graminees de la flore belgique - Du Mortier, B.-C. (Barthélemy-Charles), 1797 -1878 (Impr. de J. Casterman, 1823)

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Oceanus - Woods Hole Oceanographic Institution. (Woods Hole Oceanographic Institution, 1980)

Oecology of plants : an introduction to the study of plant-communities - Vahl, M. (Martin), 1749 -1804 (Clarendon Press, 1909)

Oecology of plants : an introduction to the study of plant-communities - Warming, Eugenius, 1841 -1924 (Clarendon Press, 1909)

Oecology of plants; an introduction to the study of plant-communities - Balfour, Isaac Bayley, 1853 -1922 (Clarendon Press, 1909)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1881)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1898)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1902)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1910)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1911)

Oesterreichische botanische Zeitschrift (A. Skofitz, 1914)

Oesterreichisches botanisches Wochenblatt ([L.W. Seidel], 1855)

Official guide to the museums of economic botany. No. 2, Monocotyledons and cryptogams (Printed for H.M. Stationary Off. by Eyre and Spottiswoode, 1895)

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The Ohio naturalist - Ohio Academy of Science. (Biological Club of the Ohio State University, 1908)

The Ohio naturalist - Ohio Academy of Science. (Biological Club of the Ohio State University, 1909)

The Ohio naturalist - Ohio Academy of Science. (Biological Club of the Ohio State University, 1906)

The Ohio naturalist - Ohio Academy of Science. (Biological Club of the Ohio State University, 1912)

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On the history and natural arrangement of insects - Shuckard, William Edward, 1802 -1868 (Printed for Longman, Brown, Green & Longman's Paternoster Row, 1840)

On the history and natural arrangement of insects - Shuckard, William Edward, 1802 -1868 (Printed for Longman, Orme, Brown, Green, & Longmans [etc.], 1840)

On the instincts and habits of the solitary wasps - Peckham, Elizabeth G. (Elizabeth Gifford), 1854 -1940 (Published by the state, 1898)