TY - BOOK ID - 91716313 TI - Conservation and the gospel of efficiency : the progressive conservation movement, 1890-1920 PY - 1999 SN - 0822957027 1306963214 0585043914 0822972034 PB - Pittsburgh, Pennsylvania : University of Pittsburgh Press, DB - UniCat KW - Conservation of natural resources KW - Environmental policy KW - History. KW - United States UR - https://www.unicat.be/uniCat?func=search&query=sysid:91716313 AB - ER -