HarperP91'

@article{DBLP:journals/tcs/HarperP91,
  author    = {Robert Harper and
               Robert Pollack},
  title     = {Type Checking with Universes},
  journal   = {Theor. Comput. Sci.},
  volume    = {89},
  number    = {1},
  year      = {1991},
  pages     = {107-136},
  ee        = {http://dx.doi.org/10.1016/0304-3975(90)90108-T},
  bibsource = {DBLP, http://dblp.uni-trier.de}
}