Columbia subject headings:
Harvard subject headings:
Ṣanʻāʼ (Yemen)--History--Early works to 1800.
Ṣanʻāʼ (Yemen)--History.
Yemen (Republic)--History--Early works to 1800.
Yemen (Republic)--History.
Princeton subject headings:
Ṣanʻāʼ (Yemen)--History.
Yemen (Republic)--History.