Weinstein & Suomi (1961)
Also: Weinstein & Suomi 1961
Analysis of satellite infrared radiation measurements on a synoptic scale
Weinstein, M., & Suomi, V. E. (1961). Analysis of satellite infrared radiation measurements on a synoptic scale. Monthly Weather Review, 89(11), 419-428. Link to paper
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.