Analysis of information sources in references of the Wikipedia article "Мітра" in Ukrainian language version.
... the Persian affiliation of the Mysteries is acknowledged in the earliest literary reference to them. This is by the Latin poet Statius who, writing about 80 CE., described Mithras as one who "twists the unruly horns beneath the rocks of a Persian cave". Only a little later (c. 100 CE.) Plutarch attributed an Anatolian origin to the Mysteries, for according to him the Cilician pirates whom Pompey defeated in 67 BCE. "celebrated certain secret rites, amongst which those of Mithras continue to the present time, having been first instituted by them".