@book{25011,
	author = {O'Harra, Cleophas C. and Coolbaugh, Melville Fuller,},
	title = {The cement resources of the Black hills.},
	year = {1908.},
	series = {Bulletin no. 8.  South Dakota school of mines.  Departments of geology, chemistry, mining and metallurgy},
	address = {Rapid City, S.D.,}
}