Reference
Daniel Borowski, Martin F. Price, Erik Gloersen (2011): Delineating mountain areas in Europe: the principles used for the ESPON GEOSPECS project and their foundation in previous research – IGF-Forschungsberichte (Instituts für Interdisziplinäre Gebirgsforschung [IGF]) (Institute of Mountain Research) – 4: 440 - 445.