.blockquote enlarges a quotation to 1.25rem. The HTML specification puts attribution outside the quotation, so wrap both in a <figure> and give the source <figcaption class="blockquote-footer">, which adds a grey em dash. Bootstrap 4 2,007 used a <footer> inside the blockquote; move it out when you upgrade, and replace .text-right with .text-end. The listing combines the typography classes from the last three subsections.
<link rel="stylesheet"
href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.8/dist/css/bootstrap.min.css">
<div class="p-3">
<h1 class="display-4">Display 4</h1>
<h2 class="h5">An h2 styled as .h5 <small class="text-body-secondary">faded</small></h2>
<p class="lead">Nobody pulls themselves up by their <span class="mark">bootstraps</span>
alone. <span class="small">Most of us get help.</span></p>
<p><abbr title="Cascading Style Sheets" class="initialism">css</abbr> utilities:
<i class="fst-italic">italic</i>, <s class="text-decoration-line-through">struck</s>.</p>
<figure class="text-end">
<blockquote class="blockquote"><p>Simplicity is prerequisite for reliability.</p></blockquote>
<figcaption class="blockquote-footer">Edsger W. Dijkstra</figcaption>
</figure>
</div>