Convergence and Stability of Optimal Two-step Fourth-order and its Expanding to Sixth Order for Solving Nonlinear Equations. Eur. J. Pure Appl. Math. [Internet]. 2022 Jul. 31 [cited 2024 May 2];15(3):971-9. Available from: https://ejpam.com/index.php/ejpam/article/view/4397