| Clue | Source | Date |
|---|---|---|
| It's never made the charts | ||
| Without a plan, United fell asleep around start of match | ||
| Named pup negligently; not yet investigated | ||
| Named pup negligently; not yet investigated | ||
| Not charted | LA Times Daily | 23 Oct 2019 |
| Not charted | The Washington Post | 23 Oct 2019 |
| Not charted | ||
| Not yet charted, as a route | ||
| Not in the atlas | ||
| Like the human genome, before the 1990s | ||
| Like terra incognita |