| Source | Notes |
| IGI | Completed for all counties of England and Wales (03/92 release of the IGI). |
| The Tordoff Book of Death by Ruth Keyworth | Completed for April 1997 edition. |
| The Tordoff Book of Marriages by Ruth Keyworth | Completed for April 1997 edition |
| War Casualties recorded by the Commonwealth War Graves Commission | Completed. |
| North of England Mining Accident Victims 1859-1899 | Confirmed no Tordoffs listed. |
| 'Convicts in Western Australia 1850 - 1887' [DICTIONARY OF WESTERN AUSTRALIANS VOLUME IX] by Rica Erickson & Gillian O'Mara | Completed. |
| Sherburn Hospital Registers: Marriages 1695-1837 | Confirmed no Tordoffs listed. |
| Durham Executions 1732-1909 | Confirmed no Tordoffs listed. |
| Joiner Marriage Index (Durham & N Yorks) | Confirmed no Tordoffs listed. |
| Victorian Pioneer Index 1837-1888 (Australia) | Confirmed no Tordoffs listed. |