Understanding the origins of mobile app vulnerabilities: a large-scale measurement study of free and paid apps. - Watanabe, Takuya; Akiyama, Mitsuaki; Kanei, Fumihiro; Shioji, Eitaro; Takata, Yuta; Sun, Bo; Ishii, Yuta; Shibahara, Toshiki; Yagi, Takeshi; Mori, Tatsuya (2017)