Authors: Helmut Karl Omar Ranne

Citation: Helmut Karl et Omar Ranne, Regional policy and the environment : the case of Germany, European environment , 11(2), 2001, pp. 103-111

Authors: Helmut Karl Helmut Kramer-Eis

Citation: Helmut Karl et Helmut Kramer-eis, Contaminated sites environmental and regional problems in Germany, European environment , 7(5), 1997, pp. 149-155

Authors: Helmut Karl Carsten Orwat

Citation: Helmut Karl et Carsten Orwat, Environmental labelling in Europe: european and national tasks., European environment , 9(5), 1999, pp. 212-220