ref: the citation's HTML anchor identifier, when different from its default. When set, |ref=ID generates an anchor with the given ID (the id attribute in the citation's <cite id="ID"> HTML tag). Setting |ref=ID identifies the template as a target and allows wikilinking to full references, especially useful with short-form citations like shortened notes and parenthetical referencing. The default anchor ID is suitable for use with {{sfn}} and {{harv}} templates.