Fedorovič, Šandor Fedir, Oleksandr Koval’, és Ûrìj Oleksandrovič Ostapec’. 2009. „The Social Mechanisms of Establishing Tourist Economic Organizations”. Acta Sana 4 (2):30-34. https://ojs.bibl.u-szeged.hu/index.php/actasana/article/view/18406.