Panasiuk, Aleksander. “FINANCING TOURISM DEVELOPMENT OF ENVIRONMENTALLY VALUABLE AREAS IN REGIONAL OPERATIONAL PROGRAMMES IN THE EUROPEAN UNION FINANCIAL PERSPECTIVES FOR 2007-2013 AND 2014-2020”. Economics and Environment, vol. 61, no. 2, Apr. 2017, p. 10, https://ekonomiaisrodowisko.pl/journal/article/view/280.