Havik T, Ertesvåg S. Systematic review and classification of: Olweus Bullying Prevention Program (OBPP) – A School-Wide Program Against Bullying and Antisocial Behavior (2. ed.). ungsinn [Internet]. 2020 May 14 [cited 2026 Aug. 16];12(1). Available from: https://septentrio.uit.no/index.php/ungsinn/article/view/7584