| Europa League 1965/1966 - Appearances as Referee |  |
 |
 |
||||
| 27/04/1966 | FC Barcelona | - | Chelsea FC | 2:0 | - | - | - |
| Europa League 1965/1966 - Appearances as Referee | |
|
|
||||
| 27/04/1966 | FC Barcelona | - | Chelsea FC | 2:0 | - | - | - |
| Complete name: | Karl Keller |
| Born: | 01/04/1923 |
| Place of birth: |
Switzerland |
| Residence: | Basel |
| Nationality: |
Switzerland |