@techreport	{ etreetr,
  author	= "Tiankai Tu and Julio Lopez and David O'Hallaron",
  title		= "The {Etree} Library: A System for Manipulating Large Octrees
		   on Disk",
  institution	= "Carnegie Mellon School of Computer Science",
  year		= 2003,
  address	= "Pittsburgh, PA",
  month		= "July",
  number	= "CMU-CS-03-174"
}