@InProceedings{	  BeigelGH90stacs,
  title		= "Counting Classes: Thresholds, Parity, Mods, and Fewness",
  year		= "1990",
  volume	= "415",
  pages		= "49--57",
  publisher	= "Springer",
  address	= "Berlin",
  series	= "Lecture Notes in Computer Science",
  booktitle	= "STACS 90 (Rouen, 1990)",
  doi		= "10.1007/3-540-52282-4_31",
  author	= "Beigel, Richard and Gill, John and Hertrampf, Ulrich"
}