A warning on the determination of the halo mass
  We summarize our studies on the determination of the mass of the dark matter
halo, based on observations of rotation curves of test particles or of the
gravitational lensing. As we show, it is not uncommon that some studies on the
nature of dark matter include extra assumptions, some even on the very nature
of the dark matter, what we want to determine!, and that bias the studies and
the results obtained from the observation and, in some cases, imply an
inconsistent system altogether.
