Journal of the Mathematical Society of Japan, vol. 66, no. 3, page. 957 - 979, 2014-07
MATHEMATISCHE NACHRICHTEN, vol. 281, no. 9, page. 1264 - 1272, 2008-09
STUDIA MATHEMATICA, vol. 178, no. 1, page. 63 - 82, 2007-03
JOURNAL OF INEQUALITIES AND APPLICATIONS, vol. 3, no. 3, page. 303 - 311, 1999-01