Mayewski, P. A., Spencer, M. J. and Lyons, W.B., 1992, A review of glaciochemistry with particular emphasis on the recent record of sulfate and nitrate. In Trace Gases and the Biosphere, Papers arising from the 1988 OIED Global Change Institute, Snowmass, CO., Moore III, Berrien and David Schimel, eds, 177-199.