Siderophile metal fallout to Greenland from the 1991 winter eruption of Hekla (Iceland) and during the global atmospheric perturbation of Pinatubo by Gabrielli, P, Barbante, C, Plane, J, Boutron, C, Jaffrezo, J, Mather, T, Stenni, B, Gaspari, V, Cozzi, G, Ferrari, C, Cescon, P