1. Thomson, W. T., Introduction to Space Dynamics (John Wiley & Sons, Inc., New York, 1961), pp.212-218.
2. On the Annular Damper for a Freely Precessing Gyroscope
3. Synge, J. L. and Griffith, B. A., Principles of Mechanics (McGraw-Hill Book Co., Inc., New York, 1949), 2nd ed., pp.421-425.