BookO85'

BibTeX

@article{DBLP:journals/ipl/BookO85,
  author    = {Ronald V. Book and
               Friedrich Otto},
  title     = {Cancellation Rules and Extended Word Problems},
  journal   = {Inf. Process. Lett.},
  volume    = {20},
  number    = {1},
  year      = {1985},
  pages     = {5-11},
  bibsource = {DBLP, http://dblp.uni-trier.de}
}