@book{7449,
	author = {Ruffin, Edmund,},
	title = {An essay on calcareous manures;},
	publisher = {J.W. Randolph,},
	year = {1852.},
	address = {Richmond, Va.,},
	edition = {5th ed., amended and enl.},
	url = {http://hdl.loc.gov/loc.gdc/scd0001.00027623256}
}