@article{IJAMCS_2005_15_4_a0,
     author = {Hui, S. and \.Zak, S.},
     title = {Observer design for systems with unknown inputs},
     journal = {International Journal of Applied Mathematics and Computer Science},
     pages = {431--446},
     publisher = {mathdoc},
     volume = {15},
     number = {4},
     year = {2005},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IJAMCS_2005_15_4_a0/}
}