@article {1697,
	title = {Global Emissions of Nitrogen and Sulfur-Oxides from 1860 to 1980},
	journal = {Japca-the Journal of the Air \& Waste Management Association},
	volume = {39},
	year = {1989},
	pages = {180-186},
	author = {Dignon, J. and Hameed, S.}
}
