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The given Problem was:
b a a -> a 
a a a -> b b b 
b b -> a b a 
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A self-embedding rewrite structure for the given SRS is:
   b b a a --(8)-> b b a a (#919)
   OC+OC at 3
      OC: b b a a --(7)-> b b a b a a (#511)
          OC+OC at 2
             OC: b b a a --(6)-> b b b b a (#487)
                 OC+OC at 0
                    OC: b b a a --(5)-> a a a b a (#290)
                        OC+OC at 1
                           OC: b b a a --(3)-> a b b a b a (#21)
                               OC+OC at 2
                                  OC: b b --(1)-> a b a (#3)
                                      Rule
                                  OC: a a a --(2)-> b a b a (#9)
                                      OC+OC at 1
                                         OC: a a a --(1)-> b b b (#2)
                                             Rule
                                         OC: b b --(1)-> a b a (#3)
                                             Rule
                           OC: b b a --(2)-> a a (#4)
                               OC+OC at 1
                                  OC: b b --(1)-> a b a (#3)
                                      Rule
                                  OC: b a a --(1)-> a (#1)
                                      Rule
                    OC: a a a --(1)-> b b b (#2)
                        Rule
             OC: b b --(1)-> a b a (#3)
                 Rule
      OC: b a a --(1)-> a (#1)
          Rule
Hence, the SRS is non-terminating.