Definition, calculation and comparison of the "Biomass Utilization Efficiency (BUE)" of various bio-based chemicals, polymers and fuels / authors: Kerstin Iffland (nova-Institute), Dr. James Sherwood (University of York), Michael Carus (nova-Institute), Achim Raschka (nova-Institute), Dr. Thomas Farmer (University of York), Prof. Dr. James Clark (University of York) ; contributors: Prof. Dr. Jan Ravenstijn (independent consultant), Erwin Vink (NatureWorks), Dr. Kurt Wagemann (DECHEMA)