| # | Reference code | Title | Dates | Access restrictions |
|---|---|---|---|---|
| 1 | RSCDS-YS-4-1 | Letter from Donald R Mackenzie to Ysobel Stewart | 15-Feb-21 | None |
| 2 | RSCDS-YS-4-2 | Letter from G Douglas Taylor to Ysobel Stewart | 16-May-34 | None |
| 3 | RSCDS-YS-4-3 | Letter from Archibald Campbell to Yosbel Stewart | 25-Sep-35 | None |
| 4 | RSCDS-YS-4-4 | Letter from Sir Malcolm MacGregor of MacGregor to Ysobel Stewart | 14-Apr-35 | None |
| 5 | RSCDS-YS-4-5 | Letters from Ion C B Jamieson to Ysobel Stewart | 22 February 1940; c. 1940 | None |
| 6 | RSCDS-YS-4-6 | Letter from John M Duthie to Ysobel Stewart | 1948 | None |