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

Pennsylvania-German names of trees - Mell, Clayton D. (Clayton Dissinger), 1875 -1945 (Rev. P.C. Croll, 1910)

Pennsylvania trees - Illick, Joseph S. (Joseph Simon), 1884 -1967 (W.S. Ray, State Printer, 1914)

Pennsylvania trees - Illick, Joseph S. (Joseph Simon), 1884 -1967 (W. S. Ray, State Printer, 1915)

Peonies, hardy garden perennials, ornamental evergreens, shade trees, shrubs : 1937, superseding all previous issues - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Cherry Hill Nurseries, 1937)

Peonies, hardy garden perennials, ornamental evergreens, shade trees, shrubs : 1938, superseding all previous issues - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Cherry Hill Nurseries, 1938)

Peonies, hardy garden perennials, ornamental evergreens, shade trees and shrubs : 1922 issue - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Newcomb & Gauss, 1922)

Peonies, hardy garden perennials, ornamental evergreens, shade trees and shrubs : 1934 issue superseding all previous issues - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Thurlow's and Stranger, Inc, 1934)

Peonies, hardy garden perennials, ornamental evergreens, shade trees and shrubs : 1935 issue superseding all previous issues - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Thurlow's and Stranger, Inc, 1935)

Peonies, hardy garden perennials, ornamental evergreens, shade trees and shrubs : 1933 issue superseding all previous issues - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Thurlow's and Stranger, Inc, 1933)

Peonies, hardy garden perennials, ornamental evergreens, shade trees and shrubs : 1923 issue - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Newcomb & Gauss, 1923)

Peonies, hardy garden perennials, ornamental evergreens, shade trees, shrubs : 1936, superseding all previous issues - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Cherry Hill Nurseries, 1936)

Perennial flower seed [price list] - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Herbst Brothers, 1928)

Periodical catalogue of fruit & ornamental trees and shrubs, greenhouse plants, etc. : cultivated and for sale at the Horticultural and Botanic Garden of Brooklyn, corner of the Jamaica and Flabush roads, about 2 miles from the City of New York - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Andrew Parmentier, 1828)

Periodical catalogue of fruit and ornamental trees and plants, cultivated at the Highland Nurseries, Newburgh, near New York - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (A. Saul & Co)

Pesticides documentation bulletin - National Agricultural Library (U.S.) (National Agricultural Library, U.S. Dept. of Agriculture, #c 1965-1969, 1965)

Peter D. Knieskern and John Torrey correspondence, 1836-1858 - Knieskern, Peter D., 1798 -1871 (1844)

Peter's plants : with which to create anew the old-time hardy gardens - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Peter's Nursery Company, 1908)

Die Pflanzen des schlesischen Tertiärs - Reimann, H. (Preussische Geologische Landesanstalt, 1919)

Pflanzen-geographie auf physiologischer Grundlage - Schimper, A. F. W. (Andreas Franz Wilhelm), 1856 -1901 (Gustav Fischer, 1908)

Pflanzen-teratologie systematisch geordnet - Penzig, O. (Ottone), 1856 -1929 (A. Ciminago, 1894)

Die Pflanzendecke der Erde : populäre Darstellung der Pflanzengeographie für gebildete Naturfreunde - Rudolph, Ludwig, 1813 -1896 (Nicolaische Verlagsbuchhandlung, 1859)

Pflanzenphysiologie als Theorie der Gärtnerei. Für Botaniker, Gärtner, Landwirte, Forstleute und Pflanzenfreunde - Molisch, Hans, 1856 -1937 (G. Fischer, 1922)

Das Pflanzenreich :regni vegetablilis conspectus - Engler, Adolf, 1844 -1930 (W. Engelmann, 1902)

Die Pflanzenwelt Norwegens. Ein Beitrag zur Natur- und Culturgeschichte Nord-Europas - Schübeler, F. C. (Frederik Christian), 1815 -1892 (A.W. Brögger, 1873)

Die Pflanzenwelt Norwegens : ein Beitrag zur Natur- und Culturgeschichte Nord-Europas - Schübeler, F. C. (Frederik Christian), 1815 -1892 (1873)

Pharmaceutical journal and transactions - Pharmaceutical Society of Great Britain. (J. & A. Churchill, 1879)

Philadelphia Medical and Physical Journal (1806)

The Philippine journal of science - Philippines. National Science Development Board. (Bureau of Science, 1911)

The Philosophical magazine and journal : comprehending various branches of science, the liberal and fine arts, agriculture, manufactures, and commerce (R. Taylor, 1817)

Phytochemie - Rochleder, Friedrich, 1819 -1874 (W. Engelmann, 1854)

Phytogeographic survey of North America. A consideration of the phytogeography of the North American continent, including Mexico, Central America and the West Indies, together with the evolution of North American plant distribution - Harshberger, John W. (John William), 1869 -1929 (W. Engelmann, 1911)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1947)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1955)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1963)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1973)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1981)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1983)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1984)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1985)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1986)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1987)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1988)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1989)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1990)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1991)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1992)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1993)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1995)

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

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1997)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1998)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 2004)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 2005)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 2006)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 2007)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 2009)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 2022)

Phytoneuron (Guy L. Nesom, 2010)

Phytoneuron (Guy L. Nesom, 2011)

Phytoneuron (Guy L. Nesom, 2012)