Mikulčić, Matea, and Tomislav Josip Mlinarić. “Railway Capacity Enhancement With Modern Signalling Systems – A Literature Review”. Promet - Traffic&Transportation 33, no. 1 (February 5, 2021): 141-152. Accessed June 20, 2021. https://traffic.fpz.hr/index.php/PROMTT/article/view/3664.