Petroleum and Petrochemicals

Document Delivery Specialists - Petroleum and Petrochemicals

API EnCompass
http://www.lhl.lib.mo.us/pubserv/ei/encompas.htm

GeoRef (American Geological Institute)
http://www.agiweb.org/georef/dds.html

Petroleum Abstracts Document Delivery Service (University of Tulsa)
http://www.pa.utulsa.edu

Research Investment
http://www.researchinvest.com/document_delivery.htm