- FondsYapp - Papers and photographs of R. H. (Harry) Yapp
- Series2 - Correspondence
- 1 more...
- Subseries2 - Expedition to Malaysia
- Subseries3 - Letters from A.A. Robb
- Subseries4 - Davos trip
- Subseries5 - South Africa trip
- Subseries6 - 1909-10 travel
- Subseries7 - Family correspondence
- Subseries8 - Love letters from Lajla to RHY before wedding
- Subseries9 - Letters from RHY to Lajla before their wedding
- Subseries10 - Professional correspondence
- 16 more...