Păvăloiu, I. “ The Optimal Efficiency Index of a Class of Hermite Iterative Methods With Two Steps”. Rev. Anal. Numér. ThéOr. Approx., vol. 29, no. 1, Feb. 2000, pp. 83-89, https://ictp.acad.ro/jnaat/journal/article/view/2000-vol29-no1-art8.