Krustok, J.; Raadik, T.; Grossberg, M.; Giraldo, S.; Neuschitzer, M.; Lopez-Marino, S.; Saucedo, E. "Temperature dependent electroreflectance study of Cu2ZnSnSe4 solar cells" Materials Science in Semiconductor Processing 39, pp. 251 - 254. 2015 DOI: 10.1016/j.mssp.2015.04.055