Thakulsukanant, A. P. D., and A. P. D. Patanavijit. “Practical Programming Tutorial of Two Dimensional Discrete Fourier Transform (DFT) Based on MATLAB® for Both 2D Signals and Images”. Journal of Food Health and Bioenvironmental Science, vol. 9, no. 1, Jan. 2016, pp. 119-3, https://li01.tci-thaijo.org/index.php/sdust/article/view/177744.