M.M. Ameen, S.M.A. and H. Mansour, M. 2020. A Simple and General Analytical Expression for Calculating Crosstalk in Multiwaveguide Directional Couplers Using Finite Differences Method. Journal of Kufa-Physics. 11, 02 (Jan. 2020), 6–14. DOI:https://doi.org/10.31257/2018/JKP/2019/110202.