1. J. Frenkel:Zeits. Phys.,37, 243 (1926).
2. L. H. Thomas:Nature,117, 514 (1926);Phil. Mag.,3, 1 (1927).
3. A detailed discussion of the traditional theory of spinning particles, including extensive references, is given byH. C. Coeben:Classical and Quantum Theories of Spinning Particles (San Francisco, 1968).
4. H. Goldstein:Classical Mechanics (Beading, Mass., 1950).
5. M. Ostrogeadskt:Mem. Acad. St. Petersburg,6, 385 (1850);E. T. Whittaker:Treatise on the Analytical Dynamics of Particles and Rigid Bodies, 4th ed. (Cambridge, 1937), p. 265.