Frederick then served in the United States Army during the Korean War.

Entity and relation annotations:
id: 0
type: entity
value: text: Frederick
labels: <Person>
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type: entity
value: text: during the Korean War
labels: <Date>
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type: entity
value: text: the Korean War
labels: <Event>
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type: entity
value: text: the United States Army
labels: <Organization>
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type: entity
value: text: the United States
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labels: Organization:located_in:Location
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labels: Person:belongs_to_NORP:Organization
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labels: Person:participates_in:Event
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