Draganova, Galja, and Konstantin Markov. “On the Brittle Fracture of a Pin-Jointed Frame”. Ann. Sofia Univ. Fac. Math. and Inf. 89 (December 12, 1997): 193–202. Accessed November 24, 2024. https://ftl5.uni-sofia.bg./index.php/fmi/article/view/368.