New Limits on R-Parity Breakings in Supersymmetric Standard Models
  New limits on couplings $\lambda^i_{jk}{''}$, which break both the baryon number and the $R$--parity, are derived by using a new mechanism that contributes to the neutron-anti-neutron oscillation. The constraints due to proton decay and its potential phenomenology are also reexamined. 
Darwin Chang and W.-Y. Keung