@book{12468,
	author = {Gohberg, I. C. and Krein, M. G.},
	title = {Introduction to the theory of linear non selfadjoint operators},
	publisher = {American Mathematical Society,},
	year = {1969},
	series = {AMS translations of Mathematical monographs},
	address = {Providence:},
	note = {"Tr. from the Russian by A. Feinstein".}
}