@book{11341,
	author = {Marx, Robert E. and Birkhead, James W.},
	title = {Hay harvesting methods and costs,},
	publisher = {[U. S. Govt. Print. Off.]},
	year = {1951.},
	series = {U. S. Dept. of Agriculture. Circular},
	address = {Washington,},
	note = {Cover title.}
}