Autocorrelation and Power Spectral Density
[1] The Probability Course: Autocorrelation
[2] The Probability Course: Power Spectral Density
[3] Henery Stark, John W. Woods, Probability and Random Processes with Applications to Signal Processing, Third Edition, Pearson Education International
[4] Sheldon M. Ross, Introduction to Probability Models , Tenth Edition, University of Southern California Los Angeles, California