| RefNo | Title | Source |
| DF/TM/1/56/16 | Correspondence H: Hellmayr | |
| DF/TM/1/63/18 | Correspondence H: Hellmayr | |
| DF/TR/1/1/24/191 | Hellmayr, Carl [Eduard] | |
| DF/TR/1/1/28/9 | American Express Company | |
| DF/TR/1/1/26/17 | Baer, G A | |
| DF/TR/1/1/34/220 | Hellmayr, C E | |
| DF/TR/1/1/28/277 | Hellmayr, [Carl] | |
| DF/TR/1/1/27/250 | Hellmayr, [Carl] | |
| DF/TM/1/50/6 | Correspondence H: Heim; Hellmayr; Hempel; Hennicke | |
| DF/TM/1/131 | Correspondence: Lynes; Hellmayr; Meade-Waldo; Jackson; Stresemann | |
| DF/TR/1/1/26/256 | Hellmayr, [Carl] | |
| DF/TR/1/1/29/293 | Hellmayr, [Carl] [Eduard] | |
| DF/TR/1/1/25/209 | Hellmayr, [Carl] | |
| DF/TR/1/1/29/463 | Neumann, Oscar | |
| DF/TR/1/1/29/8 | American Express Company | |
| DF/TR/1/1/30/233 | Hellmayr, [Carl] [Eduard] | |
| DF/TR/1/1/31/263 | Hellmayr, [Carl] [Eduard] | |
| DF/TR/1/1/32/217 | Hellmayr, [Carl] [Eduard] | |
| DF/TR/1/1/33/231 | Hellmayr, [Carl] [Eduard] | |