LEWIŃSKI, Jerzy, Ewa MAGNUCKA-BLANDZI, and Wacław SZYC. “Shear Modulus of Elasticity for Thin-Walled Trapezoidal Corrugated Cores of Seven-Layer Sandwich Plates”. Engineering Transactions 63, no. 4 (September 30, 2015): 421–438. Accessed June 12, 2025. https://et3.ippt.pan.pl/index.php/et/article/view/309.