A Construction of Monotonically Convergent Sequences from Successive Approximations in Certain Banach Spaces. S.G. Gal Numerische Mathematik
Approximation of Continuous Functions by Monotone Sequences of Polynomials with Restricted Coefficients S.G. Gal — 1988 Publications de l'Institut Mathématique
Approximation of continuous functions by monotone sequences of generalized polynomials with restricted coefficients. Gal, S.G. — 1992 Publications de l'Institut Mathématique. Nouvelle Série