Richter68'

BibTeX

@article{DBLP:journals/jsyml/Richter68,
  author    = {Wayne Richter},
  title     = {Constructively Accessible Ordinal Numbers},
  journal   = {J. Symb. Log.},
  volume    = {33},
  number    = {1},
  year      = {1968},
  pages     = {43-55},
  bibsource = {DBLP, http://dblp.uni-trier.de}
}