Baran, E., and B. Grzebyk. “FACTORS OF TOURISM DEVELOPMENT IN LESS-FAVOURED AREAS OF THE PODKARPACKIE VOIVODSHIP”. Acta Scientiarum Polonorum. Oeconomia, Vol. 9, no. 4, Dec. 2010, pp. 15-24, https://aspe.sggw.pl//article/view/3931.