@book{1926,
	author = {Aldenderfer, Mark S. and Blashfield, Roger K.,},
	title = {Cluster analysis /},
	publisher = {Sage Publications,},
	year = {c1984.},
	address = {Beverly Hills :},
	url = {http://www.loc.gov/catdir/enhancements/fy0654/84051918-d.html}
}