Specifically, “1) the variance within clusters is low, and 2) the sequence gap among clusters is empty, i.e., intermediates are not found.,,,”
」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」」＜第２章　物質の構成粒子＞（教p19-）