Correlation of crystal quality and extreme magnetoresistance of WTe2 Mazhar N. Ali, Leslie Schoop, Jun Xiong, Steven Flynn, Quinn Gibson, Max Hirschberger, N. P. Ong and R. J. Cava EPL, 110 6 (2015) 67002 Published online: 30 June 2015 DOI: 10.1209/0295-5075/110/67002