| Clue | Source | Date |
|---|---|---|
| early models | New York Times | 16 Sep 2026 |
| Preliminary working models | Newsday | 09 Sep 2025 |
| Early 22-downs in test phase (10) | ||
| Professional to write something, initially, having got manufacturer's models | ||
| Unorthodox popes try to make models (10) | ||
| Samples for child sure to involve piano | ||
| Test models | Universal | 07 Oct 2020 |
| Some mock-ups | ||
| Preludes to mass production | ||
| Originals. |