上橫線：修订间差异

欧洲国家受到[[中世纪]][[拉丁文]]{{le|缩写标记|sigla}}影响，及至近代书写亦用上橫线为重复字母缩写标记，尤其是“mm”和“nn”。当年[[艾萨克·牛顿|牛顿]]去世后，助手妹夫{{le|孔杜伊特|John Conduitt}}写信給[[贝尔纳·勒·布耶·德·丰特奈尔|丰特奈尔]]等人的法文草稿中，即“homme”以“ho{{overline|m}}e”简略<ref>{{cite web|author= |title=Three drafts of a letter from John Conduitt to Bernard de Fontenelle offering him Conduitt's Memoir of Newton, and draft of a letter from Conduitt to Horace Walpole|url=http://www.newtonproject.ox.ac.uk/view/texts/diplomatic/THEM00148|website=The Newton Project|accessdate=|date=2004-01|language=en}}</ref>，其他文献也可见到相同做法<ref>{{cite journal |title=Selected List of Naval Matter in the Library of the Historical Society of Pennsylvania |author=Albert J. Edmunds |journal=PMHB |volume=27 |issue=1 |publisher=[[宾夕法尼亚大学出版社|University of Pennsylvania Press]] |pages=71 |url=https://www.jstor.org/stable/20086069?seq=9#metadata_info_tab_contents |date=1903 |language=en |via=JSTOR |access-date=2020-08-06 |archive-date=2020-08-12 |archive-url=https://web.archive.org/web/20200812082647/https://www.jstor.org/stable/20086069?seq=9#metadata_info_tab_contents |dead-url=no }}</ref>；而德文迄今仍保有此遺风<ref>{{cite web|author=Florian Hardwig|title=Gräfinnen|url=https://www.flickr.com/photos/hardwig/6388399531/|website=|accessdate=|date=2011-11-23||via=Flickr|language=en}}</ref><ref name="Lieder zur Weihnachtszeit">{{cite web|author=Florian Hardwig|title=Lieder zur Weihnachtszeit (1940)|url=https://fontsinuse.com/uses/11409/lieder-zur-weihnachtszeit-1940|website=Fonts in Use|accessdate=|quote=It used to be common to mark omitted double letters with an overbar, especially for 'mm' and 'nn'. These abbreviations come in handy when lyrics have to match the musical notes, see 'da kom[m]t er her'.|date=2015-12-26|language=en}}</ref>。