1. Muskhelishvili, N.I.,Some Basic Problems in the Mathematical Theory of Elasticity, Nauka, Moscow (1966). (in Russian)
2. Vinokurof, L.P.,Structure Mechanics of Bars system, Part II and III (1961). (in Russian)
3. Savin, G.N.,Stress Distribution Around Holes, Gostekhizdat (1951). (in Russian)