Spherical `Top-Hat' Collapse in general Chaplygin gas dominated
  universes
  We expand previous works on the spherical `top-hat' collapse (SC-TH)
framework in generalized Chaplygin gas (gCg) dominated universes. Here we allow
the collapse in all energetic components within the system. We analyze the
non-linear stages of collapse for various choices of parameter \alpha of the
gCg model introducing an exact formulation for the so-called effective sound
speed, $c_{eff}^2$. We show that, within the SC-TH framework, the growth of the
structure becomes faster with increasing values of \alpha.
