Charles S. Kenney, Alan J. Laub. Controllability and stability radii for companion form systems. MCSS, 1(3):239-256, 1988. [doi]
@article{KenneyL88,
title = {Controllability and stability radii for companion form systems},
author = {Charles S. Kenney and Alan J. Laub},
year = {1988},
doi = {10.1007/BF02551286},
url = {http://dx.doi.org/10.1007/BF02551286},
researchr = {https://researchr.org/publication/KenneyL88},
cites = {0},
citedby = {0},
journal = {MCSS},
volume = {1},
number = {3},
pages = {239-256},
}