Al-Saffar, Alaa A. W. “Optical Parallel Quaternary Signed Digit Multiplier For Large Scale Two-Dimensional Array Using Digit-Decomposition Plane Representation”. Iraqi Journal for Electrical and Electronic Engineering 3, no. 1 (April 30, 2007): 21–32. Accessed December 8, 2025. https://ijeee.edu.iq/ijeee/article/view/38.