Let S∗ denote the set of all
functions f(z) = z + ⋯ univalent and starlike in the unit disc U. The authors show
that integral operators of the form
with suitable restrictions on the analytic functions Φ(z) and φ(z), for suitable
choices of the constants α, β, γ, and δ, transforms S∗ into S∗. With other restrictions
on the parameters, the authors obtain transformations of the sets K, S∗×K, K ×K
into S∗. Here K denotes, as usual, the set of all f(z) = z + ⋯ univalent and convex in
U.
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