Pohrybieniuk, Janina, Antoni Krotliński, Aleksandra Dusińska, Julia Sokołowska, and Mariusz Chabowski. “Loneliness Among Surgical Patients - Measuring Levels of Loneliness Using De Jong Gierveld Loneliness Scale and Revised UCLA Loneliness Scale”. Journal of Education, Health and Sport 12, no. 12 (December 23, 2022): 303–310. Accessed June 28, 2025. https://apcz.umk.pl/JEHS/article/view/41488.