  By means of a penalization scheme due to del Pino and Felmer, we prove the
existence of single-peaked solutions for a class of singularly perturbed
quasilinear elliptic equations associated with functionals which lack of
smoothness. We don't require neither uniqueness assumptions on the limiting
autonomous equation nor monotonicity conditions on the nonlinearity. Compared
with the semilinear case some difficulties arise and the study of concentration
of the solutions needs a somewhat involved analysis in which the Pucci-Serrin
variational identity plays an important role.
