RT Article T1 Acute backpack injuries in children JF Pediatrics VO 111 IS 1 SP 163 OP 166 A1 Wiersema, Brent M. A2 Foad, Susan L. A2 Wall, Eric J. LA English YR 2003 UL https://krimdok.uni-tuebingen.de/Record/1912448831 DO 10.1542/peds.111.1.163