Historical reconstruction of Plutonium contamination in the Swiss-Italian Alps J. Gabrieli, G. Cozzi, P. Vallelonga, M. Schwikowski, M. Sigl, C. Boutron and C. Barbante E3S Web of Conferences, 1 (2013) 14001 Published online: 23 April 2013 DOI: 10.1051/e3sconf/20130114001