Pseudoscalar correlators and the problem of the chiral limit in the   compact lattice QED with Wilson fermions
  The phase diagram for the compact lattice QED with Wilson fermions is shown. We discuss different methods for the calculation of the 'pion' mass $m_{\pi}$ near the chiral transition point $\kappa_c(\beta )$. 
A. Hoferichter, V.K. Mitrjushkin and M. M\"uller-Preussker