Extraction of Solitons in Optical Fibers for the (2+1)-Dimensional Perturbed Nonlinear Schrödinger Equation Via the Improved Modified Extended Tanh Function Technique. Contemp. Math. [Internet]. 2024 Apr. 25 [cited 2025 Dec. 24];5(2):2397-410. Available from: https://ojs353.mebyme.cn/index.php/CM/article/view/4301