Nagib, N. N., A. W. Abdallah, M. S. Bahrawi, H. Osman, N. A. Mahmoud, and E. S. Mousa. “Simple Method for Measuring Small Retardance”. Themes in Applied Sciences Research 1, no. 1 (April 4, 2018): 1–3. Accessed November 29, 2022. https://knowledge-press.com/index.php/TASR/article/view/13.