Columbia subject headings:
Harvard subject headings:
Asturias (Spain)--Charters, grants, privileges.
Asturias (Spain)--History--Sources.
Asturias (Spain)--Kings and rulers--Sources.
Silo, King of Asturias, -785.
Silo, King of Asturias.
Princeton subject headings:
Silo, King of Asturias.