Hintze, Dagmar, and Johannes Will. “Multisurface Plasticity Models under Yielding conditions/Multisurface-plastizitäts-Modelle Mit Zusammengesetzten Fliessbedingungen”. Journal of Civil Engineering and Management 5, no. 5 (October 31, 1999): 329-334. Accessed July 6, 2024. https://jau.vgtu.lt/index.php/JCEM/article/view/9369.