MAYBE

Proof:
ConCon could not decide confluence of the system.
\cite{ALS94}, Theorem 4.1 does not apply.
\cite{A14}, Theorem 11.5.9 does not apply.
\cite{O02}, p. 214, Proposition 7.2.50 does not apply.
System R transformed to optimized U(R).
Call external tool:
ttt2 - trs 30
Input:
  ?1(y, x, y, z) -> G(z)
  F(x, y, z) -> ?1(x, x, y, z)
  G(A) -> F(A, B, A)
  e(x) -> f(x, x)
  f(x, y) -> x

The external tool could not decide termination.
\cite{O02}, p. 214, Proposition 7.2.50 does not apply.
System R transformed to U(R).
Call external tool:
ttt2 - trs 30
Input:
  ?1(y, x, y, z) -> G(z)
  F(x, y, z) -> ?1(x, x, y, z)
  G(A) -> F(A, B, A)
  e(x) -> f(x, x)
  f(x, y) -> x

The external tool could not decide termination.