@ARTICLE{Ish90,
  author = {Ishihara, Hajime},
  title = {An omniscience principle, the {K}{\"{o}}nig lemma and the {H}ahn-{B}anach
	theorem},
  journal = ZMLG,
  year = {1990},
  volume = {36},
  pages = {237--240},
  keywords = {bib,con}
}