Columbia subject headings:
Earth (Planet)--Crust--Congresses.
Earth (Planet)--Mantle--Congresses.
Plate tectonics--Congresses.
Harvard subject headings:
Earth (Planet)--Crust--Congresses.
Earth (Planet)--Mantle--Congresses.
Plate tectonics--Congresses
Princeton subject headings:
Earth--Crust--Congresses.
Earth--Mantle--Congresses.
Plate tectonics--Congresses.