Monographs

1. "Approximation of Continuous Functions by Positive Linear Operators", Springer Lecture Notes in Math. Vol. 293, 1972.
   
   
2. (with R. Sharpley) "Maximal Functions Measuring Smoothness", Memoirs of AMS, Vol. 293, 1984
   
   
3. (with G.G. Lorentz) "Constructive Approximation", Springer Grundlehren, Vol. 303, 1993.
   
   

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