Columbia subject headings:
Factory and trade waste--Congresses.
Groundwater--Purification--Congresses.
Reclamation of land--Congresses.
Soil pollution--Congresses.
Waste disposal sites--Congresses.
Harvard subject headings:
Factory and trade waste--Congresses
Groundwater--Purification--Congresses
Reclamation of land--Congresses
Soil pollution--Congresses
Waste disposal sites--Congresses.
Princeton subject headings:
Factory and trade waste--Congresses.
Groundwater--Purification--Congresses.
Reclamation of land--Congresses.
Soil pollution--Congresses.
Waste disposal sites--Congresses.