@article {MR1490819,
	title = {Commutators of quasinilpotents and invariant subspaces},
	journal = {Studia Math.},
	volume = {128},
	number = {2},
	year = {1998},
	pages = {159{\textendash}169},
	issn = {0039-3223},
	url = {https://doi.org/10.4064/sm-128-2-159-169},
	author = {Katavolos, A. and Stamatopoulos, C.}
}
