- Cassius Dio and Ulpian - Article by Robert L. Cleve in Ancient History Bulletin on the contrasting accounts of the regency during the reign of Severus Alexander.
- Dio Cassius - Brief biography of Cassius Dio Coccetanus from the 1911 Encyclopedia Britannica.
- Dio Cassius (c. A.D. 40 - 110) - Cassius Dio Cocceianus - PDF and hypertext selections from the 1914 Cary/Loeb translation of the Roman History.
- Lacus Curtius: Cassius Dio's Roman History - Full text by chapter of the 1914 English translation by Earnest Cary.
