Ladner75'

BibTeX

@article{DBLP:journals/jacm/Ladner75,
  author    = {Richard E. Ladner},
  title     = {On the Structure of Polynomial Time Reducibility},
  journal   = {J. ACM},
  volume    = {22},
  number    = {1},
  year      = {1975},
  pages     = {155-171},
  ee        = {http://doi.acm.org/10.1145/321864.321877},
  bibsource = {DBLP, http://dblp.uni-trier.de}
}