Gaia Hypothesis References:

Lovelock, J.E. 1979. Gaia: a new look at life on earth. Oxford University Press, Oxford.
The original scientific literature on the subject (cited in the book): Lovelock, J.E. 1972.

Gaia as seen through the atmosphere. Atmospheric Environment 6:579. J.E. Lovelock and L. Margulis. 1973.

Atmospheric homeostasis by and for the biosphere: the Gaia hypothesis. Tellus 26:2. Margulis, L. and J.E. Lovelock. 1974.

Biological modulation of the Earth's atmosphere. Icarus 21:471. Lovelock, J.E. and S.R. Epton. 1975.

The quest for Gaia. New Scientist 6 February 1975.