@book{157619,
	author = {United States},
	title = {Statistical abstract of the United States},
	publisher = {U.S. Dept. of Commerce.},
	year = {1993-},
	address = {Washington, DC},
	note = {System requirements: IBM PC or compatible (286 or better microprocessor); 640K RAM; DOS 3.3 or higher; Microsoft CD Extensions 2.0 or higher; CD-ROM drive and hard disk; VGA monitor suggested but not required, mouse optional.}
}