1. M. Becker, An elementary proof of the inverse theorem for Bernstein polynomials, Aequationes Math., to appear.
2. Global approximation theorems for Szász-Mirakjan and Baskakov operators in polynomial weight spaces;Becker;Indiana Univ. Math. J.,1978
3. M. Becker, Inverse theorems for Favard operators in polynomial weight spaces, to appear.
4. Global approximation theorems for the Szász-Mirakjan operators in exponential weight spaces;Becker,1978
5. Inverse results via smoothing;Becker,1977