[1] 日本語組版処理の要件(日本語版) ( (Japanese Layout Task Force 著, 2012-03-23 20:19:12 +09:00 版)) <http://www.w3.org/TR/jlreq/ja/#characters_not_starting_a_line>

[2] 日本語組版処理の要件(日本語版) ( (Japanese Layout Task Force 著, 2012-03-23 20:19:12 +09:00 版)) <http://www.w3.org/TR/jlreq/ja/#term.line-start-prohibition-rule>