Columbia subject headings:
Drinking water--Mexico--San Luis Potosí.
Water-supply--Mexico--San Luis Potosí.
Harvard subject headings:
Drinking water--Mexico--San Luis Potosí.
Water-supply--Mexico--San Luis Potosí.
Princeton subject headings:
Drinking water--Mexico--San Luis Potosí.
Water-supply--Mexico--San Luis Potosí.