RT Article T1 The 2015 U.S. Soccer Federation header ban and its effect on emergency room concussion rates in soccer players aged 10-13 A1 Lalji, Rahim A1 Howitt, Scott A1 Chow, Noah A1 Snider, Hayden A2 Howitt, Scott A2 Chow, Noah A2 Snider, Hayden LA English YR 2020 UL https://krimdok.uni-tuebingen.de/Record/1912447053 NO 0008-3194