The paper gives such an iterative method for special Chebyshev approxiamtions that its order of convergence is $\geq 2$. Somewhat comparable results are found in [1] and [2], based on another idea.
@article{104308, author = {Ferenc K\'alovics}, title = {A fast iteration for uniform approximation}, journal = {Applications of Mathematics}, volume = {33}, year = {1988}, pages = {269-276}, zbl = {0664.65013}, mrnumber = {0949248}, language = {en}, url = {http://dml.mathdoc.fr/item/104308} }
Kálovics, Ferenc. A fast iteration for uniform approximation. Applications of Mathematics, Tome 33 (1988) pp. 269-276. http://gdmltest.u-ga.fr/item/104308/
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