1. Buckling of variable cross-section columns: integral equation approach;Arbari;J. Struct. Engng,1991
2. Scientific paper of Genik;Genik,1950
3. Scientific paper of Jasinsky;Jasinsky,1902
4. Mathematical Methods in Engineering;Karman,1940
5. Calculation Theory and its Applications of Aseismic Structures;Guiging,1985