@inproceedings { Gutman20180919,
  author = "Gutman A.E.",
  title = "Archimedean and directionally closed cones",
  booktitle = "Дни геометрии в Новосибирске -- 2018. Международная конференция (Новосибирск, 19-22 сентября 2018 г.): Тез. докладов",
  address = "Новосибирск",
  publisher = "Изд-во Ин-та математики",
  year = "2018",
  isbn = "978-5-86134-220-9",
  pages = "15",
  annote = "A criterion is provided for a wedge to be Archimedean, which is based on the notion of closed set along a direction."
}