Skala, A., and K. Rostek. “THE CHARACTERISTICS OF EXPORTERS AMONG HIGH-TECHNOLOGY MANUFACTURERS BASED IN WARSAW”. Acta Scientiarum Polonorum. Oeconomia, Vol. 14, no. 4, Dec. 2015, pp. 127-38, https://js.wne.sggw.pl/index.php/aspe/article/view/4204.