Template:Citation Style documentation/ref2

• ref: the citation's HTML anchor identifier. 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. Defaults to the special value |ref=harv which generates an anchor identifier suitable for use with {{sfn}} and {{harv}} templates. When |mode=cs1 defaults to |ref=.
  See Template:Citation/doc § Anchors for Harvard referencing templates.