1. Barlow, R. E. and Proschan, F., Mathematical Theory of Reliability, John Wiley, 1965.
2. Barlow, R. E. and Proschan, F., Statistical Theory of Reliability and Life Testing, Silver Spring, MD, 1981.
3. Çinlar, E., Introduction to stochastic Processes, Prentice-Hall, Inc., 1975.
4. Widder, D. V., The Laplace Transforms, Princeton University Press, 1941.