Balázs, M. “A Note on the Convergence of Steffensen’s Method”. Anal. Numér. Théor. Approx. 10, no. 1 (February 1, 1981): 5–10. Accessed September 3, 2025. https://www.ictp.acad.ro/jnaat/journal/article/view/1981-vol10-no1-art1.