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References
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- IPCC. Climate Change 2013 - The Physical Science Basis. Cambridge University Press, Cambridge, 2013. ISBN 9781107415324. doi: 10.1017/CBO9781107415324. URL http://ebooks.cambridge.org/ref/id/CBO9781107415324.

- M. I. Budyko, G. Observatory, and M. Spasskaja. The effect of solar radiation variations on the climate of the Earth. Tellus XXI (1969), 7, 1968. doi: 10.1111/j.2153-3490.1969.tb00466.x

- W. D. Sellers. A Global Climatic Model Based on the Energy Balance of the Earth-Atmosphere System. Journal of Applied Meteorology, 8(3):392–400, 1969. ISSN 0021-8952. doi: 10.1175/1520-0450(1969)008<0392:AGCMBO>2.0.CO;2.

Keeling-curve
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