Y.Gao, T.Sakurai, H.Zhang, K.M.Kuzanyan, and D.Sokoloff
"Statistical Distribution of Current Helicity in Solar Active Regions over the Magnetic Cycle"
Mon. Not. Roy. Astron. Soc., 433, 1648-1658, 2013
T.Ishii, T.Kawate, Y.Nakatani, S.Morita, K.Ichimoto, and S.Masuda
"High-Speed Imaging System for Solar-Flare Research at Hida Observatory"
Publ. Astron. Soc. Japan, 65, 39-48, 2013
"Long-Term Synoptic Observations of the Sun at the National Astronomical Observatory of Japan"
eds. P. Cally, R. Erdelyi, and A. Norton, J. Phys. Conf. Ser., 440, 012041, 2013
T.Sakurai, Y.Gao, and K.Kuzanyan
"Magnetic Helicity as a Probe of Magnetic Flux-Tube Dynamics in the Solar Interior"
in 'Solar and Astrophysical Dynamos and Magnetic Activity', eds. A.G.Kosovichev, E.de Gouveia Dal Pino, and Y.Yan, IAU Symp., 294, 301-306, 2013