Mann et al. (1998)
Also: Mann et al. 1998
Global-scale temperature patterns and climate forcing over the past six centuries
Mann, M.E., Bradley, R.S. & Hughes, M.K. (1998). Global-scale temperature patterns and climate forcing over the past six centuries. Nature. 392(6678),779-787. Article
https://doi.org/10.1038/33859
References
All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.