Columbia subject headings:
Art, Prehistoric--Africa.
Petroglyphs--Africa.
Rock paintings--Africa.
Harvard subject headings:
Petroglyphs--Egypt.
Petroglyphs--Sahara.
Rock paintings--Egypt.
Rock paintings--Sahara.
Princeton subject headings:
Petroglyphs--Egypt.
Petroglyphs--Sahara.
Rock paintings--Egypt.
Rock paintings--Sahara.