1. A generalized discrete transform;Ahmed,1971
2. Spectrum analysis of random data;Borgman,1973
3. Statistical properties of Fast Fourier transform coefficients computed from real valued covariance-stationary periodic random sequences;Borgman,1973
4. What is the Fast Fourier Transform?;Cochran,1967
5. An algorithm for the machine calculation of complex Fourier Series;Cooley;Mathematics of Computation,1965