Baruk A, Goliszek A. A VALUABLE NATURAL AREA AS A SYSTEM MARKETING PRODUCT VERSUS EXPECTATIONS OF TOURISTS AS ACTIVE PURCHASERS. aspe [Internet]. 2019Mar.30 [cited 2024Dec.22];18(1):5-12. Available from: https://js.wne.sggw.pl/index.php/aspe/article/view/1923