Shao, Xuemei. 1992. ?Statistical Relationships Between Tree Growth And Climate In Western North America?. Geoscience. Geoscience. University of Arizona. http://ezproxy.library.arizona.edu/login?url=http://proquest.umi.com/pqdweb?did=746968761&sid=9&Fmt=2&clientId=43922&RQT=309&VName=PQD.

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