Jaram, Slavko, and Krešimir Acinger. “Razmjena poštanskih pošiljaka Jugoslavije Sa Svijetom U 1979-1988.”. Promet - Traffic&Transportation 2, no. 4 (1): 215-221. Accessed August 30, 2025. http://traffic.fpz.hr/index.php/PROMTT/article/view/1114.