Columbia subject headings:
Rome--History--Period of military anarchy, 235-284.
Rome--Politics and government--30 B.C.-284 A.D.
Harvard subject headings:
Rome--History--Period of military anarchy, 235-284.
Rome--Politics and government--30 B.C.-284 A.D.
Princeton subject headings:
Emperors--Succession--Rome.
Rome--History--Period of military anarchy, 235-285.