[1] CLINTON WOODS, TUXEDO PK, NY 10987 USA
[2] UNIV OSLO, INST GEOL, N-0316 OSLO, NORWAY
[3] UNIV MAINE, DEPT PLANT BIOL & PATHOL, ORONO, ME 04469 USA
[4] UNIV MAINE, INST QUATERNARY STUDIES, ORONO, ME 04469 USA
[5] SERV NACL GEOL & MINERIA, SANTIAGO, CHILE
[6] COLUMBIA UNIV, LAMONT DOHERTY EARTH OBSERV, PALISADES, NY 10964 USA
[7] UNIV BERN, INST GEOL, CH-3012 BERN, SWITZERLAND
[8] UNIV MAINE, DEPT GEOL SCI, ORONO, ME 04469 USA