1. Helgason, S., Groups and Geometric Analysis, Orlando: Academic Press, 1984. Translated under the title Gruppy i geometricheskii analiz, Moscow: Mir, 1987.
2. Bers, L., John, F., and Schechter, M., Partial Differential Equations, New York, 1964. Translated under the title Uravneniya s chastnymi proizvodnymi, Moscow: Mir, 1966.