Das Pflanzenreich :regni vegetablilis conspectus - Engler, Adolf, 1844 -1930 (W. Engelmann, 1922)

Die Pflanzenwelt der peruanischen Anden in ihren Grundzügen dargestellt - Weberbauer, A. (August), 1871 -1948 (W. Engelmann, 1911)

Pharmaceutical journal and transactions - Pharmaceutical Society of Great Britain (J. & A. Churchill, 1866)

Philadelphia flower & garden show - Pennsylvania Horticultural Society. (The Society, 1977)

Philadelphia flower show - Pennsylvania Horticultural Society. (The Society, 1988)

Philadelphia flower show - Pennsylvania Horticultural Society. (The Society, 1996)

Physiological plant anatomy - Haberlandt, Gottlieb, 1854 -1945 (Macmillan and Co, 1914)

Physiological plant anatomy - Haberlandt, Gottlieb, 1854 -1945 (MacMillan, 1914)

The physiology of plants; a treatise upon the metabolism and sources of energy in plants - Pfeffer, W. (Wilhelm), 1845 -1920 (Clarendon press, 1900)

The physiology of reproduction - Marshall, F. H. A. (Francis Hugh Adam), 1878 -1949 (Longmans, Green and Co, 1910)

The physiology of reproduction - Marshall, F. H. A. (Francis Hugh Adam), 1878 -1949 (Longmans, Green, and co, 1922)

The physiology of reproduction - Marshall, F. H. A. (Francis Hugh Adam), 1878 -1949 (Longmans, 1922)

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, 1949)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1948)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1966)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1967)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1968)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1969)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 1972)

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

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, 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, 1991)

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, 1998)

Phytologia - Moldenke, Harold N. (Harold Norman), 1909 -1996 (H.A. Gleason and H.N. Moldenke, 2011)

Phytoneuron (Guy L. Nesom, 2011)

Phytoneuron (Guy L. Nesom, 2012)

The pineal organ; the comparative anatomy of median and lateral eyes, with special reference to the origin of the pineal body; and a description of the human pineal organ considered from the clinical and surgical standpoints - Gladstone, Reginald John, 1865 - (Williams & Wilkins, 1940)

Plant catalogue : orchids, palms, ferns, foliage, and flowering plants, chrysanthemums, hardy plants and shrubs - Henry G. Gilbert Nursery; Seed Trade Catalog Collection. (Pitcher & Manda, 1894)

Plant culture; a working hand-book of every day practice for all who grow flowering and ornamental plants in the garden and greenhouse - Oliver, George W. (George Watson), 1858 -1923 (A. T. De La Mare Printing and Publishing Co., Ltd, 1909)

Plant culture; a working handbook of every day practice for all who grow flowering and ornamental plants in the garden and greenhouse - Hottes, Alfred Carl, 1891 -1955 (A. T. De La Mare Co., Inc, 1921)