^Rome's Enemies (1): Germanics and Dacians (Men at Arms Series, 129) by Peter Wilcox and Gerry Embleton,1982,page 20,"... people, as were the Phrygians and those Thracians living north ... the solid crest of a 'Phrygian'-type helmet as a running pattern, as shown on the pedestal reliefs; ..."
^The Army of Alexander the Great (Men at Arms Series, 148) by Nicholas Sekunda and Angus McBride,1992,page 6,"... Philip gave them heavy armour-cuirasses and helmets of the `Phrygian' type-and he further developed the new tactical formations of Jason of Pherai ..."