@article{Rud:66a,
  journal = {Rev. Roumaine Math. Pures Appl.},
  volume = {11},
  title = {On solving {B}oolean equations in the theory of graphs},
  author = {Rudeanu, Sergiu},
  year = {1966},
  fjournal = {Acad\'emie de la R\'epublique Populaire Roumaine. Revue Roumaine
              de Math\'ematiques Pures et Appliqu\'ees},
  pages = {653--664},
}