1. A. B. Antonevich, “Elliptic Pseudodifferential Operators with a Finite Group of Shifts”, Izv. Math., 7:3 (1973), 661–673.
2. A. Antonevich, M. Belousov, and A. Lebedev, Functional Differential Equations. II. C*-Applications. Part 2. Equations with Discontinuous Coefficients and Boundary Value Problems. Pitman Monographs and Surveys in Pure and Applied Mathematics 95, Longman, Harlow, 1998.
3. A. V. Lebedev, “Quasi-Crossed Products and an Isomorphism Theorem for C*-Algebras Associated with Quasi-Representations of Discrete Groups”, Dokl. Akad., 40:5 (1996), 40–43.
4. V. E. Nazaikinskii, A. Yu. Savin, and B. Yu. Sternin, Elliptic Theory and Noncommutative Geometry. Nonlocal Elliptic Operators. Operator Theory: Advances and Applications, 183. Advances in Partial Differential Equations (Basel), Birkhäuser Verlag, Basel, 2008.
5. B. Yu. Sternin, “On a Class of Nonlocal Elliptic Operators for Compact Lie Groups. Uniformization and Finiteness Theorem”, Cent. Eur. J. Math., 9:4 (2011), 814–832.