RT Article T1 Adolescents at risk for violence JF Educational psychology review VO 7 IS 1 SP 7 OP 39 A2 Powell, Ken A2 Sleet, David A2 Kolbe, Lloyd LA English YR 1995 UL https://krimdok.uni-tuebingen.de/Record/1639399798 K1 Jugendliche K1 Gewaltbereitschaft