Ivanov89'

BibTeX

@article{DBLP:journals/jsyml/Ivanov89,
  author    = {Lyubomir Ivanov},
  title     = {Abstract Hierarchies and Degrees},
  journal   = {J. Symb. Log.},
  volume    = {54},
  number    = {1},
  year      = {1989},
  pages     = {16-25},
  bibsource = {DBLP, http://dblp.uni-trier.de}
}