A performance study of an electron-tracking Compton camera with a compact system for environmental gamma-ray observation. (4th June 2015) - Mizumoto, T.; Tomono, D.; Takada, A.; Tanimori, T.; Komura, S.; Kubo, H.; Matsuoka, Y.; Mizumura, Y.; Nakamura, K.; Nakamura, S.; Oda, M.; Parker, J.D.; et al.