| GMD | Text |
| Classification | 823.25 QUI |
| Publisher | London, William Morrow Company, c2019. |
| Subject | Female friendship -- Fiction.World War, 1939-1945 -- Women -- England -- Fiction.World War, 1939-1945 -- Cryptography -- Fiction. |
| Description | 624, 24 p ; 24 cm |
| ISBN | 9780062943477 |