@article{Kwa∂nik:1989,
  author  = "M. Kwa∂nik and D. Michalak",
  title   = "The join of graphs and the binding minimality",
  journal = "»asopis pro PžstovŠnŪ Matematiky",
  volume  = "Vol. 114",
  number  = "no 3",
  pages   = "262--275",
  year    = "1989",
}