| M. O’Driscoll (Brighton, UK) | BS46 |
| C. Obst (Mödling, AT) | P151, P376, P459 |
| B. Quesada Ocete (Mainz) | P446 |
| C. Oeing (Heidelberg) | BS35, BS37 |
| H. Oelert (Mainz) | V206 |
| P. O'Gara (London, UK) | BS31 |
| O. Oldenburg (Bad Oeynhausen) | V301, P430 |
| L. Olesch (München) | P437 |
| K. M. Olsson (Hannover) | PP135 |
| A. Ongherth (Göttingen) | BS34 |
| M. Orban (München) | P140 |
| K. Ostermann (Berlin) | P436 |
| H. Oswald (Hannover) | P169 |
| R. Ott (Krefeld) | P424 |
| F. Ouyang (Hamburg) | PP127, P153, P389, P394, P395, P396, P397, P398, P403, P404, P416, P438, P439, P453, P473 |