Peter S. Ashton Sarawak fieldwork papers - Ashton, Peter S. (Peter Shaw), 1934 - (1963)

Pflanzengeographie - Diels, Ludwig, 1874 -1945 (G. J. Göschen, 1908)

Pflanzengeographie - Diels, Ludwig, 1874 -1945 (G.J. Göschen, 1908)

Pflanzengeographie - Diels, Ludwig, 1874 -1945 (G.J. Göschen, 1918)

Das Pflanzenreich :regni vegetablilis conspectus - Engler, Adolf, 1844 -1930 (W. Engelmann, 1914)

Die Pflanzenstoffe, botanisch-systematisch bearbeitet ; chemische Bestandteile und Zusammensetzung der einzelnen Pflanzenarten, Rohstoffe und Produkte. Phanerogamen - Wehmer, C. (Carl), 1858 -1935 (G. Fischer, 1911)

Die Pflanzenwelt Ost-Afrikas und der Nachbargebiete - Engler, Adolf, 1844 -1930 (D. Reimer, 1895)

Phasmid studies - Phasmid Study Group. (Phasmid Study Group, 2009)

The Philippine journal of science - Philippines. National Science Development Board. (Bureau of Science, 1906)

The Philippine journal of science - Philippines. National Science Development Board. (Bureau of Science, 1907)

The Philippine journal of science - Philippines. National Science Development Board. (Bureau of Science, 1908)

The Philippine journal of science - Philippines. National Science Development Board. (Bureau of Science, 1909)

The Philippine journal of science - Philippines. National Science Development Board. (Bureau of Science, 1910)

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

The Philippine journal of science - Philippines. National Science Development Board. (Bureau of Science, 1914)