@incollection{MelRud:76,
  publisher = {North-Holland},
  address = {Amsterdam},
  title = {Geometry of {$3$}-rings},
  author = {Melter, Robert A. and Rudeanu, Sergiu},
  year = {1976},
  booktitle = {Lattice theory (Proc. Colloq., Szeged, 1974)},
  pages = {249--269. Colloq. Math. Soc. J\'anos Bolyai, Vol. 14},
}