1. Isaac Newton,Sir Isaac Newton's “Mathematical Principles of Natural Philosophy” and his “System of the World,” translation by Andrew Motte, revised with an Appendix by Florian Caiori, 2 vols. (University of California Press, Los Angeles, 1966),I, 6.
2. See Ref. —, I. The quoted statement is inII, 545.
3. E. Mach,Die Mechanik in ihrer Entwicklung historisch-kritisch dargestellt, 4th edn. (Brockhaus, Leipzig, 1901).
4. A. Einstein,Ann. Phys. 49, 769 (1916).
5. See, e.g., G. Mana and G. Zosi,Riv. Nuovo Cimento 18, 1 (1995).