| Clue | Source | Date |
|---|---|---|
| Offerer of $5.2 million for 65 Big Apple libraries (3/12/1901) | Newsday | 15 Mar 2020 |
| 19th-century steel industry philanthropist who built an eponymous concert hall | LA Times Daily | 28 Jan 2019 |
| 19th-century steel industry philanthropist who built an eponymous concert hall | The Washington Post | 28 Jan 2019 |
| 19th-century steel industry philanthropist who built an eponymous concert hall | ||
| "The Steel King" (1835-1919) |