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

Die Pflanzenwelt - Warburg, Otto, 1859 -1938 (Bibliographisches Institut, 1913)

Die Pflanzenwelt Afrikas, insbesondere seiner tropischen Gebiete : Grundzge der Pflanzenverbreitung im Afrika und die Charakterpflanzen Afrikas - Engler, Adolf, 1844 -1930 (W. Engelman, 1910)

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

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)