Shao, Y. ., and S. . Wang. “Truncation Error Analysis of a Pre-Asymptotic Higher-Order Finite Difference Scheme for Maxwell’s Equations”. Applied Computational Electromagnetics Society Journal (ACES), vol. 30, no. 02, Aug. 2021, pp. 167-70, https://journals.riverpublishers.com/index.php/ACES/article/view/10651.