Dodge, Richard Archie. 1963. ?Investigtions Into The Ecological Relationships Of Ponderosa Pine In Southeast Arizona?. Botany. Botany. University of Arizona. http://ezproxy.library.arizona.edu/login?url=http://proquest.umi.com/pqdweb?did=763081241&sid=6&Fmt=1&clientId=43922&RQT=309&VName=PQD.