| Clue | Source | Date |
|---|---|---|
| Always in the public domain [no repeated letters] | Newsday | 10 Aug 2018 |
| ... that has no repeated letters | New York Times | 08 Oct 2015 |
| Public-domain [no repeated letters] | Newsday | 22 Mar 2015 |
| Like book titles and ingredient lists | Wall Street Journal | 05 Jan 2015 |
| Public-domain [no repeated letters] | ||
| ... that has no repeated letters |