Shortened footnote and citation:
{{sfn | Jens | 2016 | p=}}
* {{cite book | last=Jens | first=Inge | title=Langsames Entschwinden | publisher=Rowohlt | publication-place=Reinbek bei Hamburg | date=2016-02-26 | isbn=978-3-498-03344-6 | language=de}}
Named reference:
<ref name="s669">{{cite book | last=Jens | first=Inge | title=Langsames Entschwinden | publisher=Rowohlt | publication-place=Reinbek bei Hamburg | date=2016-02-26 | isbn=978-3-498-03344-6 | language=de | page=}}</ref>