1. Duduchava, R.: On bisingular integral operators with discontinuous coefficients.Mathematics USSR, Sbornik 30, 515?537, 1976. In Russian:Matematicheskii Sbornik 101, 4, 584?609, (1976).
2. Duduchava, R.: On the index of bisingular operators. I.Mathematische Nachrichten 91, 431?460 (1979). In Russian.
3. Duduchava, R.:Integral equations with fixed singularities. Teubner, Leipzig 1979. In Russian: Integral equations of convolution type with discontinuous presymbols, singular integral equations with fixed singularities and their applications to some problems of mechanics,Trudi Tbiliskogo Mathematicheskogo Instituta im. A. M. Razmadze Academii Nauk Gruzinskoi SSR 60, 1?135, 1979
4. Duduchava, R.: On general singular integral operators of the plane theory of elasticity.Rendiconti Sem. Mat. Univers. e Politecn. Torino 42, 15?41 (1984). In Russian:Trudi Tbilisskogo Matematicheskogo Instituta im. A. M. Razmadze Academii Nauk Gruzinskoi SSR 82, 45?89 (1986).
5. Duduchava, R.: On algebras generated by convolutions and discontinuous functions.Integral Equations and Operator Theory 10, 505?530 (1987).