| Clue | Source | Date |
|---|---|---|
| Highway gunk | Newsday | 23 Feb 2021 |
| Street sealer | The Washington Post | 24 Jun 2020 |
| Street sealer | LA Times Daily | 24 Jun 2020 |
| What WD-40 can get off your car | Newsday | 29 Feb 2020 |
| Highway gunk | New York Times | 09 Dec 2018 |
| Highway gunk | ||
| It may get stuck on your car | ||
| Pothole filler |