1. Timoshenko, S., and Young, D. H., Advanced Dynamics, 1st Ed., pp.190-220; McGraw-Hill Book Company, Inc., New York, 1948.
2. von Karman, Th., and Biot, M. A., Mathematical Methods in Engineering, 1st Ed., pp.162-210, 388-404;McGraw-Hill Book Company, Inc., New York, 1940.