1. 1) Mayer, J.R. (1868) Celestial dynamics. In The Correlation and Conservation of Forces (ed. by Youmans, E.L.). D. Appleton and Co., New York, pp. 239–243.
2. 2) Waterston, J.J. and Rayleigh, L. (1892) On the physics of media that are composed of free and perfectly elastic molecules in a state of motion. Philos. Trans. R. Soc. Lond., A 183, 1–79. This article was submitted in 1845 and accepted in 1892.
3. 3) von Helmholtz, H. (1856) LXIV. On the interaction of natural forces. Lond. Edinb. Dubl. Phil. Mag. J. Sci. 11, 489–518.
4. 4) Kelvin, W.T. (1862) On the age of the Sun’s heat. Macmillan’s Mag. 5, 388–393.
5. 5) Darwin, C. (1859) On the Origin of the Species by Means of Natural Selection (1st ed.). John Murray, London.