Limits to consumption : sustainable consumption considering planetary boundaries / by Dr. Monika Dittrich, Axel Liebich, Birte Ewers, Anja Kathan, Sonja Limberger (ifeu - Institut für Energie- und Umweltforschung gGmbH, Heidelberg), Dr. Karl Schoer (SSG, Wiesbaden), Johannes Müller (Ecoinvent, Zurich (Switzerland)) ; on behalf of the German Environment Agency ; report performed by: ifeu - Institut für Energie- und Umweltforschung gGmbH, Heidelberg ; edited by: Section III - Dr. Michael Bilharz