J. Rivera
Last tournaments played
| Tournament | Date | Elo Avg. | Country |
| Amsterdam ol (Men) fin-B | 09/??/1954 | 0 | Netherlands |
| Amsterdam ol (Men) pre-IV | 09/??/1954 | 136 | Netherlands |
Most Played Openings as White
| ECO | Opening | Games |
| E61 | King's Indian defence, 3.Nc3 | 2 games |
| E81 | King's Indian, Saemisch, 5...O-O | 1 games |
| D87 | Gruenfeld, exchange, Spassky variation | 1 games |
| E28 | Nimzo-Indian, Saemisch variation | 1 games |
Most Played Openings as Black
| ECO | Opening | Games |
| C90 | Ruy Lopez, closed (with ...d6) | 1 games |
| E18 | Queen's Indian, old main line, 7.Nc3 | 1 games |
| A50 | Queen's pawn game | 1 games |
| E41 | Nimzo-Indian, 4.e3 c5 | 1 games |


Netherlands