1. Ralph Abraham and Jerrold E. Marsden. Foundations of Mechanics. The Benjamin/Cummings Publishing Company, Reading, Massachusetts, second edition, 1978.
2. James L. Anderson. Relativity principles and the role of coordinates in physics. In Hong-Yee Chiu and William F. Hoffmann, editors, Gravitation and Relativity, pp. 175–194. W.A. Benjamin, Inc., New York and Amsterdam, 1964.
3. James L. Anderson. Principles of Relativity Physics. Academic Press, New York, 1967.
4. Julian Barbour. On general covariance and best matching. In Craig Callender and Nick Huggett, editors, Physics Meets Philosophy at the Planck Scale – Contemporary Theories in Quantum Gravity, pp. 199–212. Cambridge University Press, Cambridge (England), 2001.
5. Elie Cartan. Sur les varietes a connexion affine et la théorie de la relativité généralisée. Annales Scientifiques de l’École Normale Supérieure, 40:325–412, 1923.