[11] 箇条書き、見出しの數字。
::marker 擬似要素[2] CSS3 Generated and Replaced Content Module ( ( 版)) http://www.w3.org/TR/2003/WD-css3-content-20030514/#block
[3] CSS Generated Content Module Level 3 ( ( 版)) http://dev.w3.org/csswg/css3-content/#block-markers-the-marker-pseudo-element
[4] NOTE-css-potential-19970819 ( ( 版)) http://www.w3.org/TR/NOTE-css-potential-19970819#elementId=1030143
[5] Web Applications 1.0 r8663 Rename 'list marker' and 'scope marker' to just 'marker' for consistency and clarity, and cross-reference them all ( ( 版)) http://html5.org/r/8663
[6] Need a way to styling the disclosure triangle of the <details> (or <summary>) element · Issue #722 · whatwg/html ( 版) https://github.com/whatwg/html/issues/722
3.10 順序文字
順序付き箇条書きにおける各箇条項目の先頭に付ける,順序を表す文字。
3.27 付加文字
順序文字の前及び/又は後ろに付ける文字。