| RefNo | Title | Source |
| DF/ZOO/230/23/332 | Hamilton, Major Gerald Barrett | |
| DF/ZOO/233/1/1/6 | Correspondence Ba - Br | |
| DF/ZOO/200/39/35 | Barrett-Hamilton, G | |
| DF/ZOO/200/53/32 | Barrett Hamilton, Gerald Edwin Hamilton | |
| DF/ZOO/232/3/1 | Barrett-Hamilton, Mrs M: Correspondence | |
| DF/TR/1/1/25/194 | Hamilton, [Gerald] [Edwin] [Hamilton] Barrett | |
| DF/TR/1/1/26/234 | Hamilton, P G [E?] Barrett | |
| DF/TR/1/1/29/269 | Hamilton, G E Barrett | |
| DF/ZOO/230/22/119-126 | Hamilton, Major Gerald Barrett- | |
| DF/ZOO/232/6/7/1/16 | Barrett-Hamilton, Mrs M. | |
| DF/ZOO/200/39/34 | Barrett-Hamilton, G | |
| DF/ZOO/200/51/524 | Barrett-Hamilton | |
| DF/ZOO/255/1/2/5 | Barrett- Hamilton, Gerald Edwin Hamilton (Ireland) | |
| DF/ZOO/230/5/152 | Barrett-Hamilton, G E | |
| DF/TM/1/61/9 | Correspondence B: Baron; Barrett-Hamilton; Barrow | |
| DF/ZOO/200/39/36 | Barrett-Hamilton, G | |
| DF/ZOO/200/39/32 | Barrett-Hamilton, G | |
| DF/TM/1/32/8 | Correspondence B: Barnes; Baron; Barrett-Himilton; Bartlett | |
| DF/TR/1/1/24/177 | Hamilton, P G E[?] Barrett- | |
| DF/ZOO/232/6/10/7/11 | Hamilton, G.E.H. Barrett- | |
| DF/ZOO/200/118/36 | Atkinson, Miss Rosalind | |
| DF/ZOO/230/5/154 | Harmer, S F | |
| DF/ZOO/200/63/11 | Barrett-Hamilton, Mrs M (Waterford, Ireland) | |
| DF/ZOO/232/1/8/11 | Barrett-Hamilton | |
| DF/ZOO/200/65/8 | Barrett-Hamilton, Mrs M (Waterford, Ireland) | |
| DF/ZOO/232/3 | Barrett-Hamilton, Mrs M: Correspondence | |
| DF/ADM/1000/99 | Reports and letters 1914 | |