https://www.dropbox.com/s/ypj19pijtfpy6r5/Constructing-Reg-Net-to-relating-to-Variation-to-prac-Tools--20140130-i0ccam.ppt https://www.dropbox.com/s/m35zmnehw17ls17/Constructing-Reg-Net-to-relating-to-Variation-to-prac-Tools--20140130-i0ccam.pdf