Analysis of information sources in references of the Wikipedia article "Trebonianus Gallus" in English language version.
None of the identifications of specific emperors proposed to date are truly convincing... The highly divergent coinage of the emperors of this period lends credibility to the possibility that the subject is in fact Trebonianus Gallus.
As had been stipulated by other scientists, the head does not compare to any other imperial portrait proposed. Moreover, the denomination of other heads kept in Rome, supposedly representing this Emperor, remains questionable...