1. C. B. Biezeno, Über die Bestimmung der “Durchschlagkraft” einer schwachgekrümmten, kreisförmigen Platte, Z.A.M.M. 15, 10-22 (1935)
2. V. I. Feodosev, On the stability of a spherical shell under the action of an external uniform pressure, (in Russian), Prikl. Mat. Mek. (1) 18, 35-42 (1954)
3. On the minimum buckling load for spherical shells;Friedrichs, K. O.,1941
4. A nonlinear theory of bending and buckling of thin elastic shallow spherical shells;Kaplan, A.;NACA Tech. Note,1954