## On new classes of integral operators.(English)Zbl 0942.30007

Let $${\mathcal A}$$ be the class of normalized functions $$f(z) = z + a_{2}z^{2} + \dots,$$ analytic in the unit disk, and let $$S ^{*} \subset {\mathcal A}$$ be the class of starlike functions. The author considers the classes $$N ^{*} (n) = D ^{n} S ^{*}$$, where $$D^{n}f = z (1-z)^{-n-1}*f(z),$$ $$n=0,1,\dots$$, is the Ruscheweyh derivative.
Coefficient estimates and some inclusion and radius results are obtained for these classes. There are several misprints in the paper, for instance, $$N ^{*} (1) \neq S ^{*},$$ moreover, if $$n>0$$, then $$N ^{*}(n)$$ contains non-univalent functions.

### MSC:

 30C45 Special classes of univalent and multivalent functions of one complex variable (starlike, convex, bounded rotation, etc.)