Mayewski, P.A., Meeker, L.D., Whitlow,S., Twickler, M.S., Morrison, M.C., Grootes, P.M., Bond, G.C., Alley, R.B., Meese, D.A., Gow, A.J., Taylor, K.C., Ram, M. and Wumkes, M., 1994, Changes in atmospheric circulation and ocean ice cover over the North Atlantic during the last 41,000 years, Science 263: 1747-1751.