1. Murozumi, M., Chow, T. J. & Patterson, C. C. Geochim. cosmochim. Acta 33, 1247–1294 (1969).
2. Peel, D. A. in The Environmental Record in Glaciers and Ice Sheets (eds Oeschger, H. & Langway, C. C. Jr) 207–223 (Wiley, Chichester, 1989).
3. Boutron, C. F. & Görlach, U. in Metal Speciation in the Environment (eds Broekaert, J. A. C., Gücer, S. & Adams, F.) 137–151 (Springer, Berlin, 1990).
4. Wolff, E. W. Antarct. Sci. 2, 189–205 (1990).
5. Boutron, C. F. in National Perspectives on Global Metal Cycling (eds Hutchinson, T. C., Gordon, C. A. & Meema, K. ) 241–258 (Wiley Eastern, New Delhi, 1991).