HOKKAIDO MATHEMATICAL JOURNAL《北海道数学杂志》(一年三期)。Hokkaido Mathematical Journal, one of the world-leading mathematical academic journals available in English, is published by the Department of Mathematics, Hokkaido University. The journal grew out of Series I, Mathematics, originally published from 1930 to 1972 as part of the Journal of Faculty of Science, Hokkaido University. In 1972, we started our own publication-what is now known as Hokkaido Mathematics Journal. Our department publishes the journal three times a year, with an annual volume comprising a total of nearly 500 pages. Each volume contains about 25 excellent research papers by mathematicians without regard to their fields, nationalities, or affiliations.