Meinshausen et al. (2009)
Also: Meinshausen et al. 2009
Greenhouse-gas emission targets for limiting global warming to 2 °C
Meinshausen, M., Meinshausen, N., Hare, W., Raper, S.C., Frieler, K., Knutti, R., Frame, D.J. & Allen, M.R. (2009). Greenhouse-gas emission targets for limiting global warming to 2 °C. Nature. 458(7242),1158-1162. Article
https://doi.org/10.1038/nature08017
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.