@InCollection{	  Hertrampf97fct,
  title		= "Polynomial Time Machines Equipped with Word Problems over
		  Algebraic Structures as their Acceptance Criteria",
  year		= "1997",
  volume	= "1279",
  pages		= "233--244",
  publisher	= "Springer",
  address	= "Berlin",
  series	= "Lecture Notes in Computer Science",
  booktitle	= "Fundamentals of computation theory ({K}rak{\'o}w, 1997)",
  doi		= "10.1007/BFb0036187",
  author	= "Hertrampf, Ulrich"
}