The unifiability problem in ground AC theories

It is shown that unifiability is decidable in theories presented by a set of ground equations with several associative-communicative symbols (ground AC theories). This result applies, for instance, to finitely presented commutative semigroups, and it extends the authors' previous work (P. Narendran and M. Rusinwithch, 1991) where they gave an algorithm for solving the uniform word problem in ground AC theories.<
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