@TechReport{	  kuf07tr,
  author	= "Manfred Kufleitner",
  type		= "Technical report",
  title		= "A Proof of the Factorization Forest Theorem",
  institution	= "{F}ormale {M}ethoden der {I}nformatik, {U}niversit{\"a}t
		  {S}tuttgart",
  number	= "2007/05",
  pages		= "4",
  month		= "10",
  year		= "2007",
  address	= "Germany"
}