http://wwwhep.physik.uni-freiburg.de/fp/origin/origin_help/16_CurveFitting.pdf

http://www.ece.mcmaster.ca/~xwu/part5.pdf

http://www.math.odu.edu/~jhh/chs5.pdf

http://books.google.com/books?id=YBYlCpBNo_cC&printsec=frontcover#v=onepage&q&f=false

http://people.csail.mit.edu/bkph/courses/papers/Synthetic_Aperture_Microscopy/Non_Harmonic_Sinusoids.pdf