Claeys, Philippe (California Univ. Davis, CA, United States)
Alvarez, Walter (California Univ. Berkeley., United States)
Smit, Jan (Vrije Univ. Amsterdam, Netherlands)
Hildebrand, A. R. (Geological Survey of Canada Ottawa, Ontario., Canada)
Montanari, Alessandro (Osservatorio Geologico di Coldigioco Aprio, Italy)