Shortened footnote and citation:
{{sfn | Knell | 2004 | p=}}
* {{cite book | last=Knell | first=Heiner | title=Bauprogramme römischer Kaiser | publisher=P. von Zabern | publication-place=Mainz | date=2004 | isbn=3-8053-3326-9 | language=de}}
Named reference:
<ref name="s056">{{cite book | last=Knell | first=Heiner | title=Bauprogramme römischer Kaiser | publisher=P. von Zabern | publication-place=Mainz | date=2004 | isbn=3-8053-3326-9 | language=de | page=}}</ref>