  The principal goal of this paper is to extend the classical problem of find
the values of $\alpha\in \C$ for which the mappings, either
$F_\alpha(z)=\int_0^z(f(\zeta)/\zeta)^\alpha d\zeta$ or
$f_\alpha(z)=\int_0^z(f'(\zeta))^\alpha d\zeta$ are univalent, whenever $f$
belongs to some subclasses of univalent mappings in $\D$, but in the case of
harmonic mappings, considering the \textit{shear construction} introduced by
Clunie and Sheil-Small in \cite{CSS}.
