On Ozeki's inequality. Izumino, Saichi; Mori, Hideo; Seo, Yuki — 1998 Journal of Inequalities and Applications [electronic only]
A Grüss-type inequality and its applications. Izumino, Saichi; Pečarić, Josip E.; Tepeš, Božidar — 2005 Journal of Inequalities and Applications [electronic only]
On an inequality of V. Csiszár and T.F. Móri for concave functions of two variables. Ivanković, Božidar; Izumino, Saichi; Pecaric, Josip E.; Tominaga, Masaru — 2007 JIPAM. Journal of Inequalities in Pure & Applied Mathematics [electronic only]