Columbia subject headings:
Castello del Monte (Italy)
Frederick II, Holy Roman Emperor, 1194-1250.
Harvard subject headings:
Castello del Monte (Italy)
Frederick II, Holy Roman Emperor, 1194-1250--Homes and haunts--Italy.
Frederick II, Holy Roman Emperor, 1194-1250--Knowledge--Great Pyramid (Egypt)
Great Pyramid (Egypt)
Princeton subject headings:
Castello del Monte (Italy)
Frederick II, Holy Roman Emperor, 1194-1250--Homes and haunts--Italy.
Frederick II, Holy Roman Emperor, 1194-1250--Knowledge--Great Pyramid (Egypt)
Great Pyramid (Egypt)