Columbia subject headings:
Air--Pollution--Economic aspects--California.
Air--Pollution--Government policy--California.
Atmospheric ozone--Reduction--Government policy--California.
Harvard subject headings:
Air--Pollution--Economic aspects--California.
Air--Pollution--Economic aspects--United States
Air--Pollution--Government policy--California.
Atmospheric ozone--Reduction--Government policy--California.
Atmospheric ozone--Reduction.
Princeton subject headings: