| Clue | Source | Date |
|---|---|---|
| They're full of jokers | ||
| Jam-packed circus vehicles | USA Today | 29 Sep 2019 |
| Jam-packed circus vehicles | ||
| High-occupancy vehicles? | New York Times | 09 Nov 2018 |
| High-occupancy vehicles? | ||
| High-occupancy vehicles? | LA Times Daily | 01 Feb 2017 |
| Sources of surprising exits | Newsday | 15 Aug 2015 |
| Sources of surprising exits |