@article {MR1810579,
	title = {Stability radii of linear differential algebraic equations},
	journal = {Vietnam J. Math.},
	volume = {27},
	number = {4},
	year = {1999},
	pages = {379{\textendash}382},
	issn = {0866-7179},
	author = {Nguyen Huu Du}
}
