William John Macquorn Rankine (1853) „On the general law of the transformation of energy,”. Proceedings of the Philosophical Society of Glasgow. 3 (5): 276—280.; reprinted in: (1)Philosophical Magazine, series 4, 5 (30):, pp. 106–117; and (2) W. J. Millar, ed., Miscellaneous Scientific Papers: by W. J. Macquorn Rankine, ... (London, England: Charles Griffin and Co., 1881), part II, pp. 203–208.
Gundlach, Jens H.; Merkowitz, Stephen M. (23. 12. 2002). „University of Washington Big G Measurement”. Astrophysics Science Division. Goddard Space Flight Center. „Since Cavendish first measured Newton's Gravitational constant 200 years ago, 'Big G' remains one of the most elusive constants in physics”CS1 одржавање: Формат датума (веза)
