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Let STλ(n, α, z0) be the class of functions o f the form
f(z) = a1z-Σamzm,
where am ≥ 0 and a1 > 0, analytic in the unit disc
E = {z :|z| < 1 ) and F(z) = 2/z∫ f(t)dt
satisfying (1-λ) F(Z0)/Z0 + λF'(Z0) = 1; 0≤λ≤1, -1<Z0<1.
such that Re {Dn+1f(Z)/Dnf(Z)} > α|Dn+1f(Z)/Dnf(Z)-1|, α≥0
where D is the Ruscheweyh derivative o f f(Z). Properties of functions in STλ(n, α Z0) such as coefficient estimate, closure theorem, extreme points and radius of convexity are determined.