1. Bochner, S., & K. Chandrasekharan: Fourier Transforms. Princeton 1949.
2. Hirschman, I. I., & D. V. Widder: The Convolution Transform. Princeton 1955.
3. Levin, J. J., & J. A. Nohel: On a system of integrodifferential equations occuring in reactor dynamics. J. Math. Mech. 9, 347?368 (1960).
4. Paley, R. E. A. C., & N. Wiener: Fourier Transforms in the Complex Domain. New York 1934.