| Clue | Source | Date |
|---|---|---|
| Ascertain, verify (4,4) | ||
| Confirm | Wall Street Journal | 21 Jul 2023 |
| Be certain | Premier Sunday | 12 Mar 2023 |
| Be positive | Premier Sunday | 23 Oct 2022 |
| Ascertain | Irish Times Simplex | 06 Jul 2020 |
| See to it | New York Times | 18 Nov 2018 |
| Leave no doubt | USA Today | 05 May 2018 |
| Leave no doubt | ||
| See to it | ||
| Guarantee | New York Times | 21 Sep 2017 |
| Double-check | Universal | 12 Apr 2017 |
| Guarantee | Eugene Sheffer | 17 Jan 2017 |
| Double-check | ||
| Guarantee | ||
| Leave no doubt | LA Times Daily | 26 Oct 2016 |
| Confirm | Wall Street Journal | 04 Sep 2015 |
| Double-check | Newsday | 11 Jun 2015 |
| Confirm | Thomas Joseph | 19 Mar 2015 |
| Confirm | ||
| Double-check | ||
| Confirm | ||
| See to it | ||
| See to it | ||
| See to it | ||
| Double-check | ||
| Take no chances |