  Many non-classicality indicators are used to measure quantum effects of
different systems. Kenfack's and Sadeghi's non-classicality indicators are
introduced in terms of the amount of Wigner function's negativities and
interferences in phase space quantum mechanics, respectively. They are,
effectively, applied for some real distribution functions. In this paper, we
compared these non-classicality indicators for the entangled state of photonic
number states in the Wigner, Husimi and Rivier representations. It is shown
that for a two-level entangled state, Sadeghi's indicator has more benefits
with respect to the Kenfack's indicator. For the two-level entangled state, we
show a correspondence between the Sadeghi's non-classicality indicator and the
Von Neumann entropy. It is also shown that for the superposition of squeezed
number state the Sadeghi's (and no Kenfack's) non-classicality indicators is
sensible with respect to the squeezing parameter for a superposition of
squeezed number states.
