2.3.2 和訳 Yasushi Masuda <y.masuda at acm.org> (February 3, 2004) 2.3.3 差分 Yasushi Masuda (May 31, 2004) 2.3.4 差分 Yasushi Masuda (September 20, 2004) 2.3.5 差分 Yasushi Masuda (April 20, 2005)