1. Sz Nagy, B., Foiaş, C.: Harmonic Analysis of Operators on Hilbert Space. Academia Kioda, Budapest (1970)
2. Nagy, B.Sz., Foiaş, C., Bercovici, H., Kérchy, L.: Harmonic Analysis of Operators on Hilbert Space, Revised and Enlarged Edition, Springer, New York, (2010)
3. Gohberg, I.C., Krein, M.G.: Introduction to the Theory of Linear Non-Self-Adjoint Operators. In: Transl. Math. Monographs, vol. 18, Amer. Math. Soc., Providence, RI, (1969)
4. Pavlov, B.S.: Dilation theory and spectral analysis of nonselfadjoint differential operators, Math. Programming and Related Questions (Proc. Seventh Winter School, Drogobych, 1974): Theory of Operators in Linear Spaces, Tsentral. Ekonom.-Mat. Inst. Akad. Nauk SSSR, Moscow, 1976, pp. 3-69
5. English transl in Amer. Math. Soc. Transl. (2) 115 (1980)