| Clue | Source | Date |
|---|---|---|
| Certain 19th-century history specialist | LA Times Daily | 14 Jun 2018 |
| Certain 19th-century history specialist | The Washington Post | 14 Jun 2018 |
| Certain 19th-century history specialist | ||
| Student of the Lincoln era | ||
| Student of the Lincoln era | ||
| Gettysburg visitor |