PT - JOURNAL ARTICLE ED - , TI - Environmental History, Retrospect and Prospect AID - 10.1525/phr.2001.70.1.55 DP - 2001 Feb 01 TA - Pacific Historical Review PG - 55--57 VI - 70 IP - 1 4099 - http://phr.ucpress.edu/content/70/1/55.short 4100 - http://phr.ucpress.edu/content/70/1/55.full