Columbia subject headings:
Harvard subject headings:
Bithynia--Politics and government--Sources.
Pliny, the Younger
Rome--Politics and government--30 B.C.-284 A.D.--Sources.
Trajan, Emperor of Rome, 53-117.
Princeton subject headings:
Authors, Latin--Correspondence.
Pliny, the Younger. Correspondence.
Trajan, Emperor of Rome, 53-117.