Krejčíř, Jaroslav, Petr Dostál, and Karel Doubravsky. “Interconnectivity Among Assessments from Rating Agencies: Using Cluster and Correlation Analysis”. Business: Theory and Practice 15, no. 3 (September 30, 2014): 261-268. Accessed January 6, 2025. https://ijspm.vgtu.lt/index.php/BTP/article/view/8370.