Makinen89'

@article{DBLP:journals/ipl/Makinen89,
  author    = {Erkki M{\"a}kinen},
  title     = {On the Subtree Isomorphism Problem for Ordered Trees},
  journal   = {Inf. Process. Lett.},
  volume    = {32},
  number    = {5},
  year      = {1989},
  pages     = {271-273},
  ee        = {http://dx.doi.org/10.1016/0020-0190(89)90056-2},
  bibsource = {DBLP, http://dblp.uni-trier.de}
}