Natural radioactivity and metal contamination of river sediments in the Calabria region, south of Italy F. Caridi, S. Marguccio, M. D’Agostino, A. Belvedere and G. Belmusto Eur. Phys. J. Plus, 131 5 (2016) 155 Published online: 20 May 2016 DOI: 10.1140/epjp/i2016-16155-x