The same year they were discovered at the Marktrock festival in Leuven, Belgium.

Entity and relation annotations:
id: 0
type: entity
value: text: the Marktrock festival
labels: <Event>
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type: entity
value: text: Leuven
labels: <Location>
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type: entity
value: text: Belgium
labels: <Location>
type: relation
to_id: 2
labels: Location:located_in:Location
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type: relation
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labels: Event:Occurs_at:Location
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