@ARTICLE{ist:muller.ma15a,
  author = {M{\"u}ller, M. A. and Liberzon, D. and Allg{\"o}wer, F.},
  title = {Norm-controllability of nonlinear systems},
  journal = {IEEE Trans.\ Automat.\ Control},
  year = {2015},
  volume = {60},
  pages = {1825-1840},
  number = {7}
}