Shortened footnote and citation:
{{sfn|Köppern|Köppern|1993|p=}}
* {{cite book | last=Köppern | first=Antje | last2=Köppern | first2=Norbert | title=It's Bungee-Time! | date=1993 | isbn=3-8231-0932-4 | language=de}}
Named reference:
<ref name="x852">{{cite book | last=Köppern | first=Antje | last2=Köppern | first2=Norbert | title=It's Bungee-Time! | date=1993 | isbn=3-8231-0932-4 | language=de | page=}}</ref>