I'm having some cases where a work has been attributed to an author by a source, but the source itself says this attribution is "dubious", or it is contesting a previous attributions as "spurious".

As I see it, the rank of the statement is not deprecated (in fact it is "normal" or even "preferred"), but I have no way of representing this "claim uncertainty" or "claim rebuttal".

Is there any hidden parameter for this or should it be addressed with a qualifier?

Cheers,

Micru