E.ON ERC contributions to sustainable energy pathways / editor Prof. Dr. rer. soc. oec. Reinhard Madlener ; lead authors / E.ON ERC co-directors Prof. Dr. ir. Dr. h. c. Rik De Doncker, Prof. Dr. rer. soc. oec. Reinhard Madlener, Prof. Dr. Antonello Monti [und 4 andere]