Wach, K., M. Maciejewski, and A. Głodowska. “U-Shaped Relationship in International Entrepreneurship: Entrepreneurial Orientation and Innovation As Drivers of Internationalisation of Firms”. Technological and Economic Development of Economy, vol. 28, no. 4, June 2022, pp. 1044–1067, doi:10.3846/tede.2022.16690.