@book{27540,
	author = {Wright, Calvert Charles, and Sprunk, G. C. and Pittsburgh Experiment Station (United States. Bureau of Mines)},
	title = {Hydrogenation of the petrographic constituents of Pittsburgh seam coal,},
	publisher = {The Pennsylvania State College, School of Mineral Industries,},
	year = {1939.},
	series = {Pennsylvania. State College Mineral Industries Experiment Station. Bulletin 26.},
	address = {State College, Pa.}
}