It references the Pied Piper of Hamelin.

Entity and relation annotations:
id: 0
type: entity
value: text: the Pied Piper of Hamelin
labels: <Person>
id: 1
type: entity
value: text: Hamelin
labels: <Location>
type: relation
to_id: 1
labels: Person:resides_at:Location
from_id: 0