20% by 2020? Economy-wide impacts of energy efficiency improvement in Germany.
Lehr, U., Lutz, C., Pehnt, M., Lambrecht, U., Seefeldt, F., Schlomann, B. & Fleiter, T.
(2011):
20% by 2020? Economy-wide impacts of energy efficiency improvement in Germany.
GWS Discussion Paper 11/2,
Osnabrück.