The vehicle fuel requirement is part of California's law intended to reduce air pollutants
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/activist-will-fight-delay-vehicle-fuels-cap-and-trade-system
[2] http://admin.indiaenvironmentportal.org.in/category/newspaper/los-angeles-times
[3] http://admin.indiaenvironmentportal.org.in/category/thesaurus/air-pollution
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/air-pollution-control
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/california
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/united-states-america-us
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/green-house-gases
[8] http://admin.indiaenvironmentportal.org.in/category/thesaurus/cap-and-trade