Columbia subject headings:
Aquifers--Caribbean Area--Congresses.
Aquifers--Puerto Rico--Congresses.
Aquifers--United States Virgin Islands--Congresses.
Groundwater flow--Puerto Rico--Congresses.
Groundwater flow--United States Virgin Islands--Congresses.
Groundwater--Caribbean Area--Congresses.
Groundwater--Puerto Rico--Congresses.
Groundwater--United States Virgin Islands--Congresses.
Harvard subject headings:
Princeton subject headings:
Aquifers--Caribbean Area--Congresses.
Aquifers--Puerto Rico--Congresses.
Aquifers--Virgin Islands of the United States--Congresses.
Groundwater flow--Puerto Rico--Congresses.
Groundwater flow--Virgin Islands of the United States--Congresses.
Groundwater--Caribbean Area--Congresses.
Groundwater--Puerto Rico--Congresses.
Groundwater--Virgin Islands of the United States--Congresses.