@inbook {MR1126276,
	title = {Decomposability of operators relative to two subspaces},
	booktitle = {Selfadjoint and nonselfadjoint operator algebras and operator theory ({F}ort {W}orth, {TX}, 1990)},
	series = {Contemp. Math.},
	volume = {120},
	year = {1991},
	pages = {77{\textendash}81},
	publisher = {Amer. Math. Soc., Providence, RI},
	organization = {Amer. Math. Soc., Providence, RI},
	url = {https://doi.org/10.1090/conm/120/1126276},
	author = {Katavolos, A.}
}
