@article {33879,
	title = {Nickel and vanadium porphyrins in Athabasca oil-sand asphaltenes},
	year = {1983},
	pages = {85},
	institution = {Abstract of Papers of the American Chemical Society},
	author = {Tooulakou, D. and Filby, R. H. and Jacobs, F. s.}
}
