Columbia subject headings:
Morocco--Relations--Songhai Empire.
Songhai Empire--Relations--Morocco.
Songhai Empire.
Harvard subject headings:
Morocco--Relations--Songhai Empire.
Songhai (African people)
Songhai Empire
Songhai Empire--Relations--Morocco.
Princeton subject headings:
Morocco--Foreign relations--Songhai.
Songhai Empire--Foreign relations--Morocco.
Songhai Empire--Foreign relations.