Staszewski, Wojciech. “The Labor Law Issues in the Treaties of Friendship and Cooperation Made by Poland With the Western European Countries After 1989”. Teka Komisji Prawniczej PAN Oddział W Lublinie, vol. 12, no. 2, Dec. 2019, pp. 337–350, doi:10.32084/tekapr.2019.12.2-26.