Rocky mountain trees; a handbook of the native species with plates and distribution maps.

MLA

Preston, Richard J. Rocky mountain trees; a handbook of the native species with plates and distribution maps. Second edition. Ames : Iowa State College Press, 1947.

APA

Preston, R. (1947). Rocky mountain trees; a handbook of the native species with plates and distribution maps. Second edition. Ames : Iowa State College Press.

Chicago

Preston, Richard J. Rocky mountain trees; a handbook of the native species with plates and distribution maps. Second edition. Ames : Iowa State College Press, 1947.