1. Complex convolution applied to non-linear problems;Weber,1956
2. Approximate Laplace transforms for nonlinear differential equations;Baycura,1968
3. D-transforms and non-linear systems analysis;Dasarathy;Journal of Sound and Vibration,1971
4. Theory of Functionals and of Integral and Integro Differential Equations;Volterra,1959
5. Frequency-domain analysis of weekly nonlinear networks;Kuo;Circuit and Systems,1977