...of nitrogen from light duty vehicles and engines manufactured during or after model (697) year 1976 shall contain standards which require a reduction of at least 90 per centum from the average of emissions of oxides of nitrogen actually measured from light duty vehicles...

...hydrocarbons from light duty vehicles and engines manufactured on or after model year 1975 [which] shall contain standards which require a reduction of at least 90 per centum from emissions of carbon monoxide and hydrocarbons allowable under this section applicable to...

...hydrocarbons from light duty vehicles and engines manufactured on or after model year 1975 [which] shall contain standards which require a reduction of at least 90 per centum from emissions of carbon monoxide and hydrocarbons allowable under this section applicable to...

...for the following language used in section 20-2 of the act. The regulation (for 1975 vehicles * * » shall contain standards which require a reduction of at least 90 per centum from emission of * * * hydrocarbons allowable under the standards applicable to light duty vehicles...

...and hydrocarbons from light duty vehicles and engines manufactured during or after model year 1975 shall contain standards which require a reduction of at least 90 per centum from emissions of carbon monoxide and hydrocarbons allowable under the standards under this...

...and hydrocarbons from light duty vehicles and engines manufactured during or after model year 1975 shall contain standards which require a reduction of at least 90 per centum from emissions of carbon monoxide and hydrocarbons allowable under the standards under this...

...(1970). 9 42 USC §1857f-l(b)(A)(l) provides that "engines manufactured during or after model year 1975 shall contain standards which require a reduction of at least 90 per centum from emissions of carbon monoxide and hydrocarbons allowable under the standards . . . applicable...

...oxides of nitrogen from light-duty vehicles and engines manufactured during or after model year 1976 shall contain standards which require a reduction of at least 90 per centum frmn the average of emissions of oxides afnitmgen actually measured from light-duly vehicles...

...oxides of nitrogen from light-duty vehicles and engines manufactured during or after model year 1978 shall contain standards which require a reduction of at least 90 per centum from the average of emissions of oxides of nitrogen actually measured from light-duty vehicles...

...and hydrocarbons from light-duty vehicles and engines manufactured during or after model year 1981 shall contain standards which require a reduction of at least 90 per centum from emissions of carbon monoxide and hydrocarbons allowable under the standards under this...