Robertson, I., Switsur, V.R., Carter, A.H.C., Barker, A.C., Waterhouse, J.S., Briffa, K.R. and Jones, P.D., 1997
Signal strength and climate relationships in 13C/12C ratios of tree-ring cellulose from oak in east England.
Journal of Geophysical Research, 102 19507-19516