Remarks on a result about hypercyclic non-convolution operators

In this paper we correct a proof by Aron and Markose in [R. Aron, D. Markose, On universal functions, J. Korean Math. Soc. 41 (2004) 65-76] for the hypercyclicity of the operator T:H(C)→H(C) given by T(f)(z)=f′(λz+b),|λ|⩾1, in the case b≠0.