  CeTA was originally developed as a tool for certifying termination proofs
which have to be provided as certificates in the CPF-format. Its soundness is
proven as part of IsaFoR, the Isabelle Formalization of Rewriting. By now, CeTA
can also be used for certifying confluence and non-confluence proofs. In this
system description, we give a short overview on what kind of proofs are
supported, and what information has to be given in the certificates. As we will
see, only a small amount of information is required and so we hope that CSI
will not stay the only confluence tool which can produce certificates.
