Columbia subject headings:
Africa, North--Civilization.
Africa, North--History--647-1517.
Africa, North--Intellectual life.
Crusades.
Harvard subject headings:
Africa, North--Civilization.
Africa, North--History--647-1517.
Africa, North--Intellectual life.
Crusades
Princeton subject headings:
Africa, North--History--647-1517.
Africa, North--Intellectual life.
Crusades--13th-15th centuries.