On Unitarity Based Relations Between Various Lepton Family Violating   Processes
  Simple "unitarity inspired" relations between two- and three-body lepton flavor violating decays are noted and discussed. In the absence of cancellations, the existing strong bounds on $\mu \to 3e$ and $ \mu\to e\gamma\gamma$ severly constrain two-body lepton flavor violating decays. 
S. Nussinov, R. D. Peccei and X. M. Zhang