@article{Rud:75b,
  journal = {Discrete Math.},
  volume = {13},
  title = {Local properties of {B}oolean functions. {II}. {I}sotony},
  year = {1975},
  fjournal = {Discrete Mathematics},
  pages = {161--183},
  number = {2},
  author = {Rudeanu, Sergiu},
}