Columbia subject headings:
Harvard subject headings:
Crusades--Fourth, 1202-1204
Istanbul (Turkey)--History--Siege, 1203-1204--Sources.
Latin Empire, 1204-1261.
Princeton subject headings:
Crusades--Fourth, 1202-1204--Sources.
Istanbul (Turkey)--History--Siege, 1203-1204--Sources.
Latin Empire, 1204-1261.