@Article{	  CronauerHVW98tcs,
  title		= "The Chain Method to Separate Counting Classes",
  journal	= "Theory Computing Systems",
  year		= "1998",
  volume	= "31",
  number	= "1",
  pages		= "93--108",
  issn		= "1432-4350",
  doi		= "10.1007/s002240000080",
  author	= "Cronauer, K. and Hertrampf, U. and Vollmer, H. and Wagner,
		  K. W."
}