| # | Cat. | Reference | Title | Year | |
|---|---|---|---|---|---|
| 1 | Arch | HOL/2/7/1/143 | Postcard from Gustav Holst to Imogen Holst | 1927 | |
| 2 | Arch | HOL/2/7/1/160 | Fragment of postcard from Gustav Holst to Imogen Holst | 1927 | |
| 3 | Arch | HOL/2/7/1/218 | Postcard from Gustav Holst to Imogen Holst | 1928 | |
| 4 | Arch | HOL/2/7/2/42 | Postcard from Gustav Holst to Imogen Holst | 1928 | |
| 5 | Arch | HOL/2/7/2/107 | Postcard from Gustav Holst to Imogen Holst | 1928 | |
| 6 | Arch | HOL/2/7/2/119 | Postcard from Gustav Holst to Imogen Holst | 1929 | |
| 7 | Arch | HOL/2/7/2/217 | Postcard from Gustav Holst to Imogen Holst | 1929 | |
| 8 | Arch | HOL/2/7/2/222 | Postcard from Gustav Holst to Imogen Holst | 1929 | |
| 9 | Arch | HOL/2/7/5/89 | Postcard from Gustav Holst to Imogen Holst at Citizen House, Bath | 1931 | |
| 10 | Arch | HOL/2/7/5/290 | Postcard from Gustav Holst to Imogen Holst | 1932 | |
| 11 | Arch | HOL/2/8/2/104/3 | Postcard from Gustav Holst to Imogen Holst | 1921 | |
| 12 | Arch | HOL/2/8/2/104/6 | Postcard from Gustav Holst to Imogen Holst | 1926 | |
| 13 | Arch | HOL/2/8/2/104/12 | Postcard from Gustav Holst to Imogen Holst | 1929 | |
| 14 | Arch | HOL/2/8/2/104/17 | Postcard from Gustav Holst to Imogen Holst | 1929 | |
| 15 | Arch | HOL/2/8/2/104/23 | Postcard from Gustav Holst to Imogen Holst | 1929 |
