| Calendar of the Clarendon state papers preserved in the Bodleian Library, 4 : 1657-1660 | | Monograph or Collective Volume | | 1932 |
| Cromwell's army : a history of the English soldier during the civil wars, and the Commonwealth and Protectorate | Adair, JohnFirth, Charles Harding, Sir, 1857-1936 | Monograph or Collective Volume | Greenhill Books | 1992 |
| Cromwell's army : a history of the English soldier during the Civil Wars, the Commonwealth and the Protectorate. Introd. by P.H. Hardacre. | Firth, Charles Harding, Sir, 1857-1936 | Monograph or Collective Volume | | 1962 |
| Papers relating to Thomas Wentworth, first Earl of Strafford. From the mss. of Dr William Knowler | | Article in Book | | 1895 |
| The regimental history of Cromwell's army | Davis, GodfreyFirth, Charles Harding, Sir, 1857-1936 | Monograph or Collective Volume | Clarendon Press | 1991 |