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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