@article{Korbicz:1986,
  author  = "J. Korbicz",
  title   = "Suboptimal state estimation algorithm for non-linear discrete-time distributed-parameter systems",
  journal = "International Journal of Systems Science",
  volume  = "Vol. 17",
  number  = "no 5",
  pages   = "725--734",
  year    = "1986",
}