1. V. Petkov, Relativity and the Nature of Spacetime, 2nd edn. (Springer, Heidelberg, 2009)
2. G. Galileo, Dialogue Concerning the Two Chief World Systems—Ptolemaic and Copernican, 2nd edn. (University of California Press, Berkeley, 1967), The Second Day
3. A. Einstein, The Meaning of Relativity: Four Lectures Delivered at Princeton University, May, 1921, in Relativity: Meaning and Consequences for Modern Physics and for our Understanding of the World, ed. by A. Einstein. With an Introduction by Tian Y. Cao. Edited by Vesselin Petkov (Minkowski Institute Press, Montreal, 2021)
4. I. Newton, The Principia: Mathematical Principles of Natural Philosophy. A New Translation by I. Bernard Cohen and A. Whitman assisted by Julia Budenz (University of California Press, Berkeley, 1999)
5. H. Minkowski, Space and time, new translation, in Spacetime: Minkowski’s Papers on Spacetime Physics, ed. by H. Minkowski. Translated by Gregorie Dupuis-Mc Donald, Fritz Lewertoff and Vesselin Petkov. Edited by V. Petkov (Minkowski Institute Press, Montreal, 2020)