KUSZ, Wojciech. Biografia Roberta Szumana widziana oczami psychiatry. Current Problems of Psychiatry, Lublin, Poland, v. 11, n. 4, p. 313–322, 2011. Disponível em: https://czasopisma.umlub.pl/cpp/article/view/2318. Acesso em: 16 dec. 2025.