Stephan-Otto, C.de la Macorra, A.2004-12-032004-12-0320012001http://hdl.handle.net/2003/200610.17877/DE290R-12410enThe American Physical SocietyPhysical Review Letters530Natural Quintessence with Gauge Coupling Unification10.1103/PhysRevLett.87.271301article (journal)