1. Volterra, V.: Theory of functionals and of integral and integro-differential equations, (Blackie 1930)
2. Wiener, N.: Nonlinear problems in random theory, (Chapman & Hall 1958)
3. ‘Measurement of the kernels of a nonlinear system by crosscorrelation’, Quarterly progress report, 60, Massachusetts Institute of Technology Research Laboratory of Electronics, January, 1961
4. ‘Measurement of a second-degree Wiener kernel in a nonlinear system by crosscorrelation’, Quarterly progress report, 65, Massachusetts Institute of Technology Research Laboratory of Electronics, April, 1962
5. Gyftopoulos, E.P., and Hooper, R.J.: ‘Signals for transfer-function measurement in nonlinear systems’, Noise analysis in nuclear systems, 1964),USAEC symposium series 4, TID—7679