@Article{Junttila:JUCS7,
  author = 	 {Tommi A. Junttila},
  title = 	 {Computational Complexity of the {Place/Transition}-Net
                  Symmetry Reduction Method},
  journal = 	 {Journal of Universal Computer Science},
  year = 	 {2001},
  volume = 	 {7},
  number = 	 {4},
  pages = 	 {307--326},
}