A Two-zone Model for Blazar Emission: Implications for TXS 0506+056 and the Neutrino Event IceCube-170922A. - Xue, Rui; Liu, Ruo-Yu; Petropoulou, Maria; Oikonomou, Foteini; Wang, Ze-Rui; Wang, Kai; Wang, Xiang-Yu (Astrophysical Journal, 2019)