Constraints on free parameters of the simplest bilepton gauge model from   the neutral kaon system mass difference
  We consider the contributions of the exotic quarks and gauge bosons to the mass difference between the short- and the long-lived neutral kaon states in $SU(3)_C \times SU(3)_L \times U(1)_N$ model. The lower bound $M_{Z'} \sim$ 14 TeV is obtained for the extra neutral gauge boson ${Z'}^0$. Ranges for values of one of the exotic quark masses and quark mixing parameters are also presented. 
F. Pisano, J. A. Silva-Sobrinho and M. D. Tonasse