Laue, M. (1911), Das Relativitätsprinzip, Braunschweig: Friedr. Vieweg & Sohn. For an account of the early history see Minguzzi, E. (2011), "The Poincaré-Einstein synchronization: historical aspects and new developments", J. Phys.: Conf. Ser., 306 (1): 012059, Bibcode:2011JPhCS.306a2059M, doi:10.1088/1742-6596/306/1/012059
Laue, M. (1911), Das Relativitätsprinzip, Braunschweig: Friedr. Vieweg & Sohn. For an account of the early history see Minguzzi, E. (2011), "The Poincaré-Einstein synchronization: historical aspects and new developments", J. Phys.: Conf. Ser., 306 (1): 012059, Bibcode:2011JPhCS.306a2059M, doi:10.1088/1742-6596/306/1/012059
Poincaré, Henri (1904–1906), "The Principles of Mathematical Physics" , Congress of arts and science, universal exposition, St. Louis, 1904, vol. 1, Boston and New York: Houghton, Mifflin and Company, pp. 604–622