Hsu W.-L; Chien Y.-C; Huang Y.-T; Yu K.J; JENG-YUH KO; Lin C.-Y; Tsou Y.-A; Leu Y.-S; Liao L.-J; Chang Y.-L; Su J.-Y; Liu Z; Wang C.-P; Terng S.-D; Hua C.-H; Lee J.-C; Yang T.-L; Kate Hsiao C.-H; Wu M.-S; Tsai M.-H; Liu M.-J; Lou P.-J; Hildesheim A; Chen C.-J; the GEV-NPC Study Group