و آر ایل:https://www.researchgate.net/profile/Julio-Gutierrez-Vega/publication/243580702/figure/fig1/AS:298509413699587@1448181598787/Color-online-Parameter-definitions-and-geometry-of-the-problem_Q320.jpg
و آر ایل:https://www.researchgate.net/figure/Color-online-Parameter-definitions-and-geometry-of-the-problem_fig1_243580702
