Karakašev, D., T. Šijakova-Ivanova, E. Karakaševa, and Z. Panov. “Stability Analysis of Rock Wedges With Multiple Sliding Surfaces”. Geologica Macedonica, Vol. 23, Apr. 2013, pp. pp.63-72, https://js.ugd.edu.mk/index.php/GEOLMAC/article/view/242.