1. Integral Operators in the Theory of Linear Partial Differential Equations;Bergman,1969
2. Solutions of linear partial differential equations of one fourth order;Bergman;Duke Math. J.,1944
3. Calculations of rectangular orthotropic plates lying on an elastic foundation with two foundation moduli and subject to static and pulsating loads;Kiselev,1962
4. New Methods for Solving Elliptic Equations;Vekua,1967