Lazarević, Dragan, Momčilo Dobrodolac, a Predrag Ravelić. „AN ANALYSIS OF THE POSTAL MARKET CONCERNING 24/7 COURIER SERVICE AVAILABILITY". Perner’s Contacts 15, no. 2 (prosinec 30, 2020). Viděno únor 9, 2023. https://pernerscontacts.upce.cz/index.php/perner/article/view/1636.