@article{BarVai:60,
  journal = {Bull. Math. Soc. Sci. Math. Phys. R. P. Roumaine (N.S.)},
  volume = {4 (52)},
  title = {Le cas limite du crit\`ere de {W}ittmeyer pour la m\'ethode de
           {G}auss-{S}eidel},
  author = {Barb{\u{a}}lat, Ioan and Vaida, Drago{\c{s}}},
  year = {1960},
  pages = {3--18},
  number = {3-4},
}