Kingdom of Srem under the rule of Stefan Dragutin was actually Lower Srem.

Entity and relation annotations:
id: 0
type: entity
value: text: Stefan Dragutin
labels: <Person>
id: 1
type: entity
value: text: Lower Srem
labels: <Location>
id: 2
type: entity
value: text: Kingdom of Srem
labels: <Organization>