00318nas a2200109   4500000000100000000000100001008004100002260002000043100001600063700003100079245009800110       2017                            d  c19 Septemb 20171 aAndrew Barr1 aAlexandra Herfroy-Mischler00aISIL's Execution Videos: Audience Segmentation and Terrorist Communication in the Digital Age