using xml document replicate paragraph if condition equals true

<fn-group>
<fn id="1"><p>For example, the <format>sixteenth-century</format> cow</p>
<p>Other new seventeenth-century cow</p>
<p>this is my text</p></fn>
<fn id="2"><p>For example, the sixteenth-century cow</p>
<p>Other new seventeenth-century cow</p>
<p>this is my text</p></fn>
<fn-group>

[condition]
if the <fn> tag contains <format> tag then the whole <fn> should be replicated right after

<fn-group>
<fn id="1"><p>For example, the <format>sixteenth-century</format> cow</p>
<p>Other new seventeenth-century cow</p>
<p>this is my text</p></fn>
<fn id="1"><p>For example, the <format>sixteenth-century</format> cow</p>
<p>Other new seventeenth-century cow</p>
<p>this is my text</p></fn>
<fn id="2"><p>For example, the sixteenth-century cow</p>
<p>Other new seventeenth-century cow</p>
<p>this is my text</p></fn>
<fn-group>