@incollection{Vai:99,
  title = {Ordered semirings and rings},
  year = {1999},
  booktitle = {Information technology (Bucharest, 1999)},
  mrnumber = {MR1730113},
  pages = {1054--1060},
  publisher = {Inforec, Bucharest},
  mrclass = {16H05 (06F25)},
  author = {Vaida, Drago{\c{s}}},
}