Columbia subject headings:
Harvard subject headings:
Continuous emission monitoring--European Economic Community countries.
Motor vehicles--European Economic Community countries--Pollution control devices.
Motor vehicles--Motors--Exhaust gas--Environmental aspects--European Economic Community countries.
Pollution--European Economic Community countries--Measurement.
Princeton subject headings:
Automobiles--European Economic Community countries--Pollution control devices.
COPERT 90 (Computer program)
Continuous emission monitoring--European Economic Community countries.
Pollution--European Economic Community countries--Measurement.