  Entanglement, one of the most intriguing aspects of quantum mechanics, marks
itself into different features of quantum states. For this reason different
criteria can be used for verifying entanglement. In this paper we review some
of the entanglement criteria casted for continuous variable states and link
them to peculiar aspects of the original debate on the famous EPR paradox.
Moreover, we give a handy expression for valuating Bell-type non-locality on
Gaussian states. We also present the experimental measurement of a particular
realization of the Bell operator over continuous variable entangled states
produced by a sub-threshold type-II OPO.
