1. Detection of the Schwarzschild precession in the orbit of the star S2 near the Galactic centre massive black hole
2. S. T. Thornton
and
J. B. Marion
, Classical Dynamics of Particles and Systems, 5th ed. (
Brooks/Cole,
Belmont, 2004), Secs. 8.4 and 8.9, pp. 291–295 and 312–316.
3. W. Rindler
, Relativity: Special, General, and Cosmological, 2nd ed. (
Oxford U. P.
Oxford, 2006), Sec. 11.9, pp. 241–245.
4. P. J. O'Donnell
, Essential Dynamics and Relativity (
CRC Press,
Boca Raton, FL, 2014), Sec. 5.8, pp. 127–129.