Collocations for authenticity - noun

cast doubt on, doubt
Some journalists have cast doubt on the authenticity of the official version of events.

check, test | confirm, establish, prove, verify

a certificate of authenticity
Despite its certificate of authenticity, the painting was found to be a fake.

a debate over the authenticity of sth
There has been some debate over the authenticity of his will.

of doubtful authenticity
a document of doubtful authenticity