HILMOLA, Olli-Pekka. Data Envelopment Analysis of Helsinki-Tallinn Transportation Chains. Promet - Traffic&Transportation, [S. l.], v. 25, n. 6, p. 575–586, 2013. DOI: 10.7307/ptt.v25i6.1196. Disponível em: https://traffic2.fpz.hr/index.php/PROMTT/article/view/2437. Acesso em: 26 aug. 2025.