Evaluation of neutrino masses from $m_{\beta\beta}$ values
  A neutrino mass matrix is considered under conditions of a CP invariance and a small reactor mixing $\theta_{13}$ angle. Absolute mass values for three neutrinos are evaluated for normal and inverted hierarchy spectra on the ground of data for oscillation mixing neutrino parameters and an effective neutrino mass $m_{\beta\beta}$ related to a probability of neutrinoless two beta decay. 
V. V. Khruschov