Chkareuli, J. L.Froggatt, C. D.Nielsen, H. B.2004-12-032004-12-0320012001http://hdl.handle.net/2003/89410.17877/DE290R-10780enThe American Physical SocietyPhysical Review Letters530Lorentz Invariance and Origin of Symmetries10.1103/PhysRevLett.87.091601article (journal)