Hossein Beikzadeh Hamid D. Taghirad Exponential nonlinear observer based on the differential state-dependent Riccati equation. 358-368 2012 9 Int. J. Autom. Comput. 4 https://doi.org/10.1007/s11633-012-0656-y https://www.wikidata.org/entity/Q115377841 db/journals/ijautcomp/ijautcomp9.html#BeikzadehT12