Columbia subject headings:
Harvard subject headings:
Agriculture--Nile River Valley.
Climatic changes--Social aspects--Nile River Valley--History--To 1500.
Nile River--History.
Water resources development--Nile River--History--To 1500.
Water-supply--Nile River Watershed--Management--History.
Princeton subject headings:
Agriculture--Nile River Valley.
Climatic changes--Social aspects--Nile River Valley--History--To 1500.
Nile River--History.
Water resources development--Nile River--History--To 1500.
Water-supply--Nile River Watershed--Management--History.