• On flatness of discrete-time nonlinear systemsKaldmäe, Arvo; Kotta, Ülle9th IFAC Symposium on Nonlinear Control Systems 2013 : Toulouse, France, 4 - 6 September 20132013 / p. 588 - 593 https://doi.org/10.3182/20130904-3-FR-2041.00017 https://www.scopus.com/sourceid/21100456158 https://www.scopus.com/record/display.uri?eid=2-s2.0-84885732008&origin=resultslist&sort=plf-f&src=s&sot=b&sdt=b&s=DOI%2810.3182%2F20130904-3-FR-2041.00017%29