Columbia subject headings:
Tapanuli Utara (Indonesia)--History.
Toba Lake (Indonesia)--History.
Toba-Batak (Indonesian people)--History.
Harvard subject headings:
Tapanuli Utara (Indonesia)--History.
Toba-Batak (Indonesian people)--Genealogy.
Toba-Batak (Indonesian people)--History.
Toba-Batak (Indonesian people)--Social life and customs.
Princeton subject headings: