<http://webisa.webdatacommons.org/30570951> <http://www.w3.org/ns/prov#wasQuotedFrom> <iu.edu> . <http://webisa.webdatacommons.org/prov/360489795> <http://www.w3.org/ns/prov#wasDerivedFrom> <http://webisa.webdatacommons.org/30570951> . <http://webisa.webdatacommons.org/30570951> <http://www.w3.org/ns/prov#value> "Covers such topics as resource depletion, population growth, endangered ecosystems, deep ecology, and the land ethic." . <http://webisa.webdatacommons.org/30570951> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://www.w3.org/ns/prov#Entity> .