TY - JOUR TI - Special Issue: Challenges for Europe 2050: Selected papers of the EUROFRAME Conference 2015 and the WWWforEurope Project DO - 10.1007/s10663-016-9358-y SP - 657 EP - 660 PY - 2016-01-01 JO - Empirica AU - Böheim, Michael AU - Oberhofer, Harald ER -