| Clue | Source | Date |
|---|---|---|
| Complaining about the covering of the book (7) | ||
| Obligatory | The Telegraph Quick | 15 Feb 2024 |
| Obligatory thing to keep a book together? (7) | ||
| Book cover | The Telegraph Quick | 05 Oct 2023 |
| Involving contractual obligation | The Times Concise | 03 May 2022 |
| Part of a book cover | Thomas Joseph | 28 Aug 2019 |
| Compulsory cover | The Sun Two Speed | 29 May 2019 |
| Mandatory | The Sun Two Speed | 29 May 2019 |
| Compulsory cover | The Telegraph Cryptic | 08 Dec 2018 |
| Obligatory. |