Advanced Three Level Approximation for Numerical Treatment of
  Cosmological Recombination
  New public numerical code for fast calculations of the cosmological
recombination of primordial hydrogen-helium plasma is presented. The code is
based on the three-level approximation (TLA) model of recombination and allows
us to take into account some fine physical effects of cosmological
recombination simultaneously with using fudge factors. The code can be found at
http://www.ioffe.ru/astro/QC/CMBR/atlant/atlant.html
