| RefNo | Title |
| DF/ZOO/200/62/26 | Montpensiar, H R H le duc de (Paris) |
| DF/ZOO/252/13/6 | Gordon, Isabella: obituary and bibliography of Dr Ole Theodore Mortensen (1868-1952) |
| DF/ZOO/252/1/9/52 | Mortensen, Theodor Jensen (Copenhagen) |
| DF/ZOO/200/62/27 | Mortensen, Ole Theodor Jensen, 1868-1952 (Copenhagen, Denmark, & Edinburgh, Scotland) |
| DF/ZOO/213/113/11 | Mortensen, T: report on Echinoidea (Volume VI/1) |
| DF/ZOO/264/1/76 | Echinodermata correspondence: Mortensen, Dr Theodor (Denmark) |
| DF/ZOO/252/1/15/13 | Mortensen, Theodor Jensen (Copenhagen) |
| DF/ZOO/200/57/40 | Mortensen, Ole Theodor Jensen, 1868-1952 (Copenhagen, Denmark, & Edinburgh, Scotland) |
| DF/ZOO/252/1/5/12 | Mortensen, Theodor Jensen (Copenhagen) |
| DF/ZOO/264/1/75 | Echinodermata correspondence: Mortensen, Dr Theodor (Denmark) |
| DF/ZOO/264/1/78 | Echinodermata correspondence: Mortensen, Dr Theodor (Denmark) |
| DF/ZOO/264/1/77 | Echinodermata correspondence: Mortensen, Dr Theodor (Denmark) |
| DF/ZOO/264/6/9 | Marion; Martens; Mortensen; Murray |