@book{12532,
	author = {Ibach, D. B. and Adams, J. Richard and United States.},
	title = {Crop yield response to fertilizer in the United States},
	publisher = {U.S. Dept. of Agriculture, Economic Research Service; [for sale by the Supt. of Docs., U.S. Govt. Print. Off.,},
	year = {1968]},
	series = {[United States. Dept. of Agriculture] Statistical bulletin},
	address = {Washington]},
	note = {Cover title.}
}