1. Kauligan, G. H., and Houseman, M. R., “Temperature Coefficient of the Moduli of Metal and Alloys Used as Elastic Elements,”Journal of Research, National Bureau of Standards, Vol. 10 (1933), p. 345.
2. Spotts, M. F.,Design of Machine Elements, fourth edition (Prentice-Hall, Englewood Cliffs, NJ, 1971), p. 217.
3. Wahl, A. M., “Mechanical Springs” (1949), p. 79.