Neutrino Mixing With Non-Zero $\theta_{13}$ In Zee-Babu Model
  The exact solution for the neutrino mass matrix of the Zee-Babu model is derived. Tribimaximal mixing imposes conditions on the Yukawa couplings, from which the normal mass hierarchy is preferred. The derived conditions give a possibility of Majorana maximal $\mathrm{CP}$ violation in the neutrino sector.   We have shown that non-zero $\theta_{13}$ is generated if Yukawa couplings between leptons almost equal to each other. The model gives some regions of the parameters where neutrino mixing angles and the normal neutrino mass hierarchy obtained consistent with the recent experimental data. 
H.N.Long and V.V.Vien
hep-ph