Then they set up rules to regulate those emissions from cars. (sciencemag.org)
The only way to do this is to first determine where that point should be and then regulate emissions as a «limited resource» in the market place. (realclimate.org)
Also, what about a debate regarding whether or not regulating emissions is the only, or best, solution to reduce our dependence on fossil fuels? (tierneylab.blogs.nytimes.com)