Physical and emotional health problems experienced by youth engaged in physical fighting and weapon carrying. oleh Sophie D Walsh, Michal Molcho, Wendy Craig, Yossi Harel-Fisch, Quynh Huynh, Atif Kukaswadia, Katrin Aasvee, Dora Várnai, Veronika Ottova, Ulrike Ravens-Sieberer, William Pickett