Resnick, Robert (1968). "Supplementary Topic B: The Twin Paradox". Introduction to Special Relativity. place:New York: John Wiley & Sons, Inc. p. 201. ISBN0-471-71725-8. LCCN67031211.. via August Kopff, Hyman Levy (translator), The Mathematical Theory of Relativity (London: Methuen & Co., Ltd., 1923), p. 52, as quoted by G.J. Whitrow, The Natural Philosophy of Time (New York: Harper Torchbooks, 1961), p. 215.
Weidner, Richard (1985). Physics. Needham Heights, MA: Allyn and Bacon. ISBN0205111556.
E. Minguzzi (2005) - Differential aging from acceleration: An explicit formula - Am. J. Phys.73: 876-880 arXiv:physics/0411233 (Notation of source variables was adapted to match this article's.)
Debs, Talal A.; Redhead, Michael L.G. (1996). "The twin "paradox" and the conventionality of simultaneity". American Journal of Physics. 64 (4): 384–392. Bibcode:1996AmJPh..64..384D. doi:10.1119/1.18252.
Debs, Talal A.; Redhead, Michael L.G. (1996). "The twin "paradox" and the conventionality of simultaneity". American Journal of Physics. 64 (4): 384–392. Bibcode:1996AmJPh..64..384D. doi:10.1119/1.18252.
Resnick, Robert (1968). "Supplementary Topic B: The Twin Paradox". Introduction to Special Relativity. place:New York: John Wiley & Sons, Inc. p. 201. ISBN0-471-71725-8. LCCN67031211.. via August Kopff, Hyman Levy (translator), The Mathematical Theory of Relativity (London: Methuen & Co., Ltd., 1923), p. 52, as quoted by G.J. Whitrow, The Natural Philosophy of Time (New York: Harper Torchbooks, 1961), p. 215.