author      = "M. Witczak and P. Prętki and J. Korbicz",
  title       = "Design and convergence analysis of first- and second-order extended unknown input observers",
  booktitle   = "Methods and Models in Automation and Robotics - MMAR 2007 : proceedings of the 13th IEEE/IFAC international conference; ISBN: 9788375180329",
  address     = "Szczecin, Polska",
  publisher   = "Szczecin, PPH Zapol, Dmochowski, Sobczyk, Spółka Jawna",
  pages       = "833--838 [CD-ROM]",
  organization = "Institute of Control Engineering, Szczecin University of Technology",
  year        = "2007",