| Date | Grid | Clue | Author | Editor |
|---|---|---|---|---|
| Sun, May 22, 2016 | 1D | Limestone areas with sinkholes and caverns | Victor Barocas and Andy Kravis | Shortz |
| Fri, Nov 15, 2013 | 9A | Rough limestone regions with sinkholes and caverns | David Woolf | Shortz |
| Sat, Dec 01, 2007 | 50A | Limestone regions with deep fissures and sinkholes | Robert H. Wolfe | Shortz |