@article {35857,
	title = {Determination of geoporphyrins in Athabasca tar sands using semi-automated chromatographic deasphaltation },
	year = {1988},
	pages = {8},
	institution = {Abstract of Papers of the American Chemical Society},
	author = {Freeman, D. H. and Angeles, R. M. and Keller, S.}
}
