1. Visual Complex Analysis;Needham,1997
2. Some Basic Problems of Mathematical Theory of Elasticity;Muskhelishvili,1953
3. Complex Variable Methods in Elasticity;England,1971
4. Theory of Elasticity of an Anisotropic Elastic Body;Lekhnitskii,1963
5. Invariant variation problems;Noether;Math. – Phys. Klasse,1918