| Link | Location |
|---|
 | Nadezhda Onishchuk | Москва, Russia |
| Toshihiro Ono | Tokyo, Giappone |
| Glenn Onos | Matthews, North Carolina, Stati Uniti |
 | Ronald Oomen | Deventer, Paesi Bassi |
 | Martijn Oost | Brussels, Belgio |
| Erik Oosterhuis | Bergschenhoek, Paesi Bassi |
| Frey Oosterlinck | Harelbeke, Belgio |
| Albert Oosthuizen | Johannesburg, Sudafrica |
| Piotr Opalacz | Kraków, Polonia |
| Pavel Oparin | Almaty, Kazakistan |
| Yulia Openysheva | Moscow online, Russia |
| Douglas Opfer | Houston, Texas, Stati Uniti |
| Bas Opgelder | Hoofddorp, Paesi Bassi |
| Heino Ophey | Karlsruhe, Germania |
| Luca Oppedisano | Turin, Italia |
