Proceedings of the United States National Museum - Smithsonian Institution (Smithsonian Institution Press, [etc.], 1885)

Proceedings of the United States National Museum - Smithsonian Institution (Smithsonian Institution Press, [etc.], 1960)

Proceedings of the United States National Museum - Smithsonian Institution (Smithsonian Institution Press, [etc.], 1961)

Proceedings of the United States National Museum - Smithsonian Institution (Smithsonian Institution Press, [etc.], 1963)

Proceedings of the United States National Museum - Smithsonian Institution (Smithsonian Institution Press, [etc.], 1966)

Proceedings-Symposium on Plant-Herbivore Interactions : Snowbird, Utah, August 7-9, 1985 - Intermountain Research Station (Ogden, Utah) (Intermountain Research Station, Forest Service, U.S. Dept. of Agriculture, 1987)

Proceedings : Symposium on the Biology of Artemisia and Chrysothamnus : Provo, Utah, July 9-13, 1984 - Intermountain Research Station (Ogden, Utah) (Intermountain Research Station, Forest Service, U.S. Dept. of Agriculture, 1986)

Prodrom der Waldstätter Gefässpflanzen - Rhiner, Joseph, 1830? -1897 (J. Bürgler, 1870)

Prodromus plantarum indiae occidentalis :hucusque cognitarum tam in oris Americae Meridionalis, quam in insulis Antillicis sponte crescentium, aut ibi diuturne hospitantium, nova genera et species hactenus ignotas complectens - Hamilton, William, 1788 -1856 (Treuttel et Würtz, 1825)

Prodromus systematis naturalis regni vegetabilis, sive, Enumeratio contracta ordinum generum specierumque plantarum huc usque cognitarium, juxta methodi naturalis, normas digesta - Candolle, Augustin Pyramus de, 1778 -1841 (Sumptibus Sociorum Treuttel et Würtz, 1866)

Prodromus systematis naturalis regni vegetabilis, sive, Enumeratio contracta ordinum generum specierumque plantarum huc usque cognitarium, juxta methodi naturalis, normas digesta - Candolle, Augustin Pyramus de, 1778 -1841 (Sumptibus Sociorum Treuttel et Würtz, 1874)