1. The Feynman Lectures on Physics;Feynman,1963
2. Discrete Numerical Methods in Physics and Engineering;Greenspan,1974
3. D. Greenspan, Technical Report No. 205, Dept. of Math., Univ. of Texas at Arlington, Arlington, Texas.
4. Energy and momentum conserving methods of arbitrary order for the numerical integration of equations of motion
5. R. A. Labudde and D. Greenspan, Int. J. Math. and Math. Sci., in press.