Person

De Ong, E. R. (Elmer Ralph), 1882-1966

Catalogue

Books
Insect, fungus and weed control / by E.R. de Ong.
De Ong, E. R. (Elmer Ralph), 1882-1966.Date: 1953
Books
Chemistry and uses of pesticides / [Elmer Ralph De Ong].
De Ong, E. R. (Elmer Ralph), 1882-1966.Date: [1956]